2020 Urban Water Management Plan Draft

MAY 2021 ANTELOPE VALLEY-EAST KERN WATER AGENCY

ANTELOPE VALLEY‐ EAST KERN WATER AGENCY 2020 Urban Water Management Plan

MAY 25, 2021

Prepared by Water Systems Consulting, Inc.

ACKNOWLEDGMENTS

This document was prepared in partnership between WSC and AVEK. WSC thanks the following people for their contributions:

Dwayne Chisam, General Manager Matt Knudson, Assistant General Manager Tom Barnes, Water Resources Manager

AVEK Board of Directors Director Keith Dyas, Division 2, President Director Frank S. Donato, Division 3, Vice President Director Shelley Sorsabal, Division 1 Director George M. Lane, Division 4 Director Robert A. Parris, Division 5 Director Audrey T. Miller, Division 6 Director Gary Van Dam, Division 7

TABLE OF CONTENTS

List of Figures ...... iv List of Tables ...... v Acronyms & Abbreviations ...... vi Executive Summary ...... ES-1 1. Introduction ...... 1-1 Urban Water Management Plan Purpose and Overview ...... 1-3 UWMP Organization ...... 1-4 UWMPs in Relation to Other Efforts ...... 1-4 Demonstration of Consistency with the Delta Plan for Participants in Covered Actions ...... 1-5 2. Plan Preparation ...... 2-1 Plan Preparation ...... 2-2 Basis for Preparing a Plan ...... 2-2 Coordination and Outreach ...... 2-2 2.3.1 Wholesale and Retail Coordination ...... 2-3 2.3.2 Coordination with Other Agencies and the Community ...... 2-3 3. System Description ...... 3-1 General Description ...... 3-2 Service Area Climate ...... 3-4 Service Area Population and Demographics ...... 3-4 4. Water Use Characterization ...... 4-1 Past and Current Water Use ...... 4-2 Projected Water Use ...... 4-4 4.2.1 Population Growth...... 4-6 4.2.2 Per Capita Demand Rebound ...... 4-6 4.2.3 Passive and Active Conservation ...... 4-9 4.2.4 Climate Change ...... 4-9 4.2.5 Groundwater ...... 4-10 4.2.6 Recycled Water ...... 4-10 4.2.7 Distribution System Water Losses ...... 4-10 4.2.8 AVEK Demand Projections ...... 4-11 4.2.9 Characteristic Five-Year Water Use ...... 4-11

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5. SBX7-7 Baseline, Targets and 2020 Compliance ...... 5-1 6. Water Supply Characterization ...... 6-1 State Water Project ...... 6-3 6.1.1 SWP Water Supply Estimates ...... 6-4 6.1.2 Groundwater Banking...... 6-6 6.1.3 Water Quality ...... 6-8 Water Exchanges and Transfers ...... 6-9 Groundwater ...... 6-11 6.3.1 Groundwater Accounting ...... 6-14 6.3.2 Water Quality ...... 6-14 Wastewater and Recycled Water ...... 6-14 6.4.1 Recycled Water Coordination ...... 6-14 6.4.2 Wastewater Collection, Treatment, and Disposal ...... 6-15 Surface Water ...... 6-16 Stormwater ...... 6-16 Desalinated Water Opportunities ...... 6-16 Future Water Projects ...... 6-16 6.8.1 New Supplemental Water Supply (per LACWD MOU) ...... 6-16 Summary of Projected Water Supplies ...... 6-17 6.9.1 Climate Change Effects ...... 6-18 Energy Intensity ...... 6-18 7. Water Supply Reliability and Drought Risk Assessment ...... 7-1 Water Supply Reliability Assessment ...... 7-2 7.1.1 Water Supply Reliability – Normal Year ...... 7-3 7.1.2 Water Supply Reliability – Single Dry Year ...... 7-4 7.1.3 Water Supply Reliability – Five Consecutive Dry Years ...... 7-5 2021–2025 Drought Risk Assessment ...... 7-7 8. Water Shortage Contingency Plan ...... 8-1 9. Demand Management Measures ...... 9-1 Demand Management Measures for Wholesale Suppliers ...... 9-2 Public Education and Outreach ...... 9-2 Water Conservation Program Coordination and Staffing ...... 9-2 Asset Management ...... 9-3 Wholesale Supplier Assistance Programs ...... 9-3 10. Plan Adoption, Submittal, and Implementation ...... 10-1 Inclusion of All 2020 Data ...... 10-2

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Notice of Public Hearing ...... 10-2 Submittal of the UWMP and WSCP ...... 10-2 Public Availability ...... 10-2 11. References ...... 11-1 Appendix A: 2020 UWMP DWR Checklist ...... A Appendix B: 2020 UWMP DWR Tables ...... B Appendix C: Delta Reliance ...... C Appendix D: Notifications and Notification List ...... D Appendix E: Adoption Resolutions ...... E Appendix F: Antelope Valley Groundwater Adjudication ...... F Appendix G: Antelope Valley Watermaster 2019 Annual Report ...... G Appendix H: Water Shortage Contingency Plan ...... H

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LIST OF FIGURES

Figure ES-1. 2011–2020 AVEK Deliveries by Type ...... ES-3 Figure ES-2. 2011–2020 AVEK Historical SWP Deliveries to Groundwater Banking Sites ...... ES-3 Figure ES-3. Projected AVEK Groundwater Banking Target Sizing ...... ES-4 Figure ES-4. 2011–2020 AVEK Drinking Water Deliveries by Source ...... ES-5 Figure ES-5. AVEK Supply and Demand Projections, Normal Year ...... ES-8 Figure ES-6. AVEK Supply and Demand Projections, Single Dry Year ...... ES-9 Figure ES-7. AVEK Groundwater Bank Storage Capacity vs. Use during Five Consecutive Dry Years ...... ES-10 Figure ES-8. 2021–2025 AVEK Drought Reliability Assessment ...... ES-11 Figure 1-1. AVEK Service Area ...... 1-2 Figure 3-1. AVEK Major Facilities ...... 3-3 Figure 4-1. 2011–2020 AVEK Deliveries by Type ...... 4-3 Figure 4-2. 2015–2020 AVEK Retailers with UWMPs GPCD for Trailing 12 Months ...... 4-8 Figure 6-1. 2011–2020 AVEK Drinking Water Deliveries by Source ...... 6-2 Figure 6-2. 2011–2020 AVEK SWP Deliveries by Type of Water ...... 6-3 Figure 6-3. 2011–2020 AVEK SWP Deliveries by Location ...... 6-4 Figure 6-4. 2011–2020 AVEK Historical SWP Deliveries to Groundwater Banking Sites ...... 6-7 Figure 6-5. Projected AVEK Groundwater Banking Target Sizing ...... 6-8 Figure 6-6. 2011–2020 AVEK Annual Exchanges and Transfers Volumes ...... 6-10 Figure 7-1. AVEK Supply and Demand Projections, Normal Year ...... 7-3 Figure 7-2. AVEK Supply and Demand Projections, Single Dry Year ...... 7-4 Figure 7-3. AVEK Groundwater Bank Storage Capacity vs. Use During Five Consecutive Dry Years ...... 7-6 Figure 7-4. 2021–2025 AVEK Drought Reliability Assessment...... 7-8

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LIST OF TABLES

Table ES-1. AVEK Service Area Current and Projected Population (DWR UWMP Table 3-1W)...... ES-2 Table ES-2. 2025-2045 AVEK Demand Projections (AFY) ...... ES-3 Table ES-3. SWP Average Yield Projections ...... ES-6 Table ES-4. Projected Water Supplies ...... ES-7 Table ES-5. AVEK Supply Projections for 2021–2025 Drought Risk Assessment ...... ES-11 Table 3-1. Precipitation, Evapotranspiration, and Temperature in AVEK Service Area ...... 3-4 Table 3-2. Current and Projected Population (DWR UWMP Table 3-1W) ...... 3-5 Table 3-3. Current and Projected Households and Employment ...... 3-5 Table 4-1. Actual Demands for Water (DWR 4-1W) (Acre-Feet per Year) ...... 4-2 Table 4-2. 2016–2020 AVEK Service Area GPCD – All Customers ...... 4-7 Table 4-3. 2025–2045 AVEK Demand Projections (AFY) ...... 4-11 Table 4-4. 2021–2025 AVEK Demand Projections (AFY) ...... 4-11 Table 6-1. California Department of Water Resources (DWR) 6-8W Actual Water Supplies (DWR 6-8W) ...... 6-2 Table 6-2. SWP Average Yield Projections ...... 6-5 Table 6-3. Table A Deliveries in Selected Drought Conditions ...... 6-5 Table 6-4. 2020 AVEK Exchanges and Transfers ...... 6-9 Table 6-5. Ramp-down Production Rights Within and Outside of AVEK’s Service Area, AFY ...... 6-11 Table 6-7. Non-Overlying Producers’ Production Rights by AVEK Customers ...... 6-12 Table 6-8. Overlying Producers’ Production Rights by AVEK Customers ...... 6-13 Table 6-9. Groundwater Volume Pumped (DWR 6-1W) ...... 6-14 Table 6-10. Retail Recycled Water Projection Within AVEK Service Area ...... 6-15 Table 6-11. Projected New Supplemental Water Supplies (per LACWD MOU) ...... 6-17 Table 6-12. Projected Water Supplies (DWR Table 6-9W) ...... 6-17 Table 6-13. 2017–2020 AVEK Energy Intensity Estimates ...... 6-18 Table 7-1. SWP Average Yield Projections ...... 7-3 Table 7-2. Multiple Dry Years Supply and Demand Comparison (DWR Table 7-4W) ...... 7-5 Table 7-3. AVEK Supply Projections for 2021–2025 Drought Risk Assessment ...... 7-7

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ACRONYMS & ABBREVIATIONS

F Degrees Fahrenheit AB Assembly Bill AF Acre Foot AFY Acre Feet per Year CIMIS California Irrigation Management Irrigation System DCR DWR SWP Delivery Capacity Report DDW SWRCB Division of Drinking Water DMM Demand Management Measure DWR California Department of Water Resources EIR Environmental Impact Report EPA United States Environmental Protection Agency ETo Reference Evapotranspiration GPCD Gallons per Capita per Day GPM Gallons per Minute MGD Million Gallons per Day RWQCB Regional Water Quality Control Board SBX7-7 Senate Bill 7 of Special Extended Session 7 SOI Sphere of Influence SWRCB State Water Resources Control Board TDS Total Dissolved Solids UWMP Urban Water Management Plan UWMP Act Urban Water Management Planning Act WSCP Water Shortage Contingency Plan WTP Water Treatment Plant WWTP Wastewater Treatment Plant

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URBAN WATER MANAGEMENT PLAN Executive Summary This section includes a lay description of the 2020 UWMP, which describes the fundamental determinations of the UWMP, including water supply reliability, challenges ahead, and strategies for managing reliability risks.

This section summarizes the 2020 Urban Water Management IN THIS SECTION

Plan (UWMP or Plan) for the Antelope Valley-East Kern Water  Outreach and Agency (AVEK or Agency). This UWMP was prepared in Engagement compliance with California Water Code requirements for  Population UWMPs, following guidance from the California Department of Projections Water Resources (DWR), and is intended to be the long-term  Water Demand Projections water resources planning reference for the Agency.  Water Sources and AVEK is a wholesale supplier of State Water Project (SWP) water Uses to the greater Antelope Valley region. SWP water is a secondary  Water Supply water source for AVEK’s customers and is used in lieu of, or in Reliability addition to, pumped groundwater.

AVEK’s service area encompasses nearly 2,400 square miles in northern Los Angeles and eastern Kern Counties as well as a small portion of Ventura County. AVEK has played a major role in the Valley’s water system since it was granted a charter by the State Legislature in 1959 and became a SWP contractor in 1962. AVEK currently provides water to 27 retail water agencies, water companies, and agricultural customers. AVEK’s mission is to deliver reliable, sustainable, and high-quality supplemental water to the region in a cost-effective and efficient manner.

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DRAFT Executive Summary

Outreach and Engagement The 2020 UWMP was prepared in a transparent manner, and AVEK actively engaged stakeholders, cities, counties, water agencies, and the public to seek and distribute information about water use, supply, and reliability to strengthen the region’s ability to assess and plan for the region’s water future. AVEK conducted a public hearing on June 8, 2021, and notified over 40 entities, including AVEK’s customers, cities, and counties within the AVEK service area, and other water and planning agencies in the region.

Population Projections AVEK provides service to incorporated and unincorporated areas of the greater Antelope Valley. The current and projected populations for AVEK’s service area (Table ES-1) were based on population projections from the Southern California Association of Governments (SCAG) for Los Angeles and Ventura Counties and the Kern Council of Governments (KCOG). The combined projections result in an average annual growth rate of 1.33%, with a high growth rate initially (2020–2025) and lower rates at end of the projection (2040–2045).

Table ES-1. AVEK Service Area Current and Projected Population (DWR UWMP Table 3-1W)

POPULATION SERVED 2020 2025 2030 2035 2040 2045 Los Angeles and Ventura Counties 270,615 288,578 306,542 324,505 342,229 359,953

Kern County 49,956 56,757 63,558 70,359 78,738 87,118

TOTAL 320,571 345,335 370,100 394,864 420,967 447,071

Notes: 1. Data for Los Angeles and Ventura Counties from SCAG 2020 Connect SoCal Regional Transportation Plan (SCAG, 2020) 2. Data for Kern County from KCOG General Land Use Plan (KCOG, 2018a).

Water Demand Projections AVEK delivers treated water from the SWP and groundwater to 23 customers, and untreated SWP water to four customers. In addition, AVEK delivers untreated SWP water to its groundwater “banks” by recharging SWP at recharge basins and storage in the groundwater basin so that AVEK can recover the water when needed. AVEK also occasionally transfers untreated SWP water to other water agencies when AVEK has surplus water available and the other agencies are in need of water. As shown in Figure ES-1, treated water deliveries to AVEK retailers were relatively consistent compared with deliveries to recharge sites and other locations. Treated water demands have increased slightly since 2017 but have not returned to the levels observed prior to 2014 following severe drought restrictions. Both recharge water deliveries and deliveries to other locations have varied significantly based on water availability, as evidenced by the high recharge volume in 2017 that coincided with high SWP allocations. Recharge deliveries are discussed further below; however, transfers are not projected in this UWMP because they are opportunistic agreements made by willing parties dependent on each party’s needs and they are the lowest priority use of AVEK’s supplies.

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Executive Summary

Figure ES-1. 2011–2020 AVEK Deliveries by Type

160,000 Untreated Water to Other Locations Untreated Water to Recharge Sites 140,000 Treated Water Deliveries

120,000 51,028

100,000 49,807 35,887 80,000 AFY 36,860 26,116 60,240 60,000 19,640 23,384 27,823 12,061 12,831 6,814 16,329 14,086 7,213 40,000 371 12,480

20,000 44,355 43,016 43,837 40,858 40,960 36,666 34,205 39,058 32,386 26,998

0 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020

Treated Water Projections To estimate demands on AVEK supplies, AVEK must first project total demand in the AVEK service area along with projected use of local supplies. The primary local supply is groundwater. AVEK developed a model to compare future supply and demand conditions under multiple supply and demand scenarios.

AVEK considered seven primary variables and applied the following assumptions for UWMP demand projections:

Population Growth Applies the population projections presented earlier in this section using comprehensive data from SCAG and KCOG.

Per Capita Demand Rebound This variable considers the extent that per capita demand, measured as gallons per capita per day (GPCD), is estimated to increase from spring 2016, which was the last year severe water use restrictions were in place by AVEK retailers. This UWMP assumes existing demands will increase from 185 GPCD in 2020 to 205 GPCD by 2030.

Passive Conservation This variable considers water savings resulting from plumbing codes and other institutionalized water efficiency measures. This UWMP assumes 0.2% per year reduction in existing demand.

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Executive Summary

Active Conservation This variable considers water saved as a direct result of programs and practices directly funded by a water utility. As a wholesaler, AVEK has less control over conservation programs implemented by its customers. Also, the potential demand impacts are not well understood from the “Conservation as a California Way of Life” legislative mandates from 2018, which require new urban water use efficiency standards by 2022. Therefore, to be conservative in this UWMP, AVEK assumes no active conservation savings, but AVEK intends to work with its customers to understand the potential implications of meeting new urban efficiency standards and plans to adapt its projections based on this and other available information once annual water use reporting starts in 2023.

Climate Change This variable considers the potential change in demand from climate change. Climate models disagree on average annual precipitation projections but agree on other hydrologic metrics relevant to water resources management, including increased evapotranspiration, which would increase irrigation demands. Based on climate change projections from DWR1, by 2030, precipitation is projected to decrease by 3% and evapotranspiration is projected to increase by 4%, which roughly equates to a net irrigation demand increase of 7%. Irrigation demands may be roughly 50% of total demand, which means that increased evapotranspiration from climate change would increase demand by 3.5% — or about 3,000 acre-feet per year (AFY) over the next 25 years — compared with a more than 40% increase in demand from population growth and unit demand rebound. For this UWMP, increased evapotranspiration is not explicitly included in the demand projections because assumptions for the other variables discussed above (growth, unit demand, and conservation) have a greater impact on the demand projections, and demand impacts from climate change are within the margin of error for the projections.

Groundwater This variable estimates the volume of pumping by AVEK customers, which would reduce the amount of AVEK water needed to meet AVEK service area demands. For this UWMP, groundwater pumping is assumed to occur at the amount of production rights described in the Stipulated Judgment (Judgment) for the 2015 Antelope Valley Groundwater Adjudication. The Judgment stipulated production rights to each party and other methods to access additional groundwater rights, such as from imported water return flows. AVEK’s customers have 12,084 AFY of production rights and have received roughly 12,000 AFY of return flow rights since 2016. Imported water return flows are projected to increase as demands increase and imported water must be used to meet those demands. Recycled Water This variable includes with and without planned recycled water use by retailers. This UWMP assumes no recycled water will be developed that offsets projected water use through 2045.

Based on the assumptions described above, AVEK estimated total service area demand projections and net demand on AVEK projections through 2045 as shown in Table ES-2.

1 https://sgma.water.ca.gov/webgis/?appid=SGMADataViewer Antelope Valley-East Kern Water Agency 2020 Urban Water Management Plan May 2021 ES-4 DRAFT

Executive Summary

Table ES-2. 2025-2045 AVEK Demand Projections (AFY)

2025 2030 2035 2040 2045 TOTAL AVEK SERVICE AREA DEMAND 73,420 80,400 83,850 87,520 91,200

NON-AVEK SUPPLIES

Groundwater, Non-AVEK Production Rights 12,080 12,080 12,080 12,080 12,080

Groundwater, Non-AVEK Return Flows 16,900 17,330 19,890 20,230 21,530

NON-AVEK SUPPLIES TOTAL 28,980 29,410 31,970 32,310 33,610

NET AVEK SERVICE AREA DEMAND 44,440 50,990 51,880 55,210 57,590 Groundwater Recharge Projections AVEK’s groundwater banking programs store surplus water available from the SWP through groundwater recharge and include recovery wells to pump stored water in times of need. AVEK’s groundwater banks include the Westside Water Bank, which started operations in 2010; the Eastside Water Bank, which started operations in 2016; the Upper Amargosa Creek Recharge Project, a partnership project that started operations in 2019; and, most recently, the High Desert Water Bank. Local recovery of SWP water from the groundwater banks has become an important source of water for AVEK to supplement annual SWP water allocations. AVEK began pumping water from the groundwater banks in 2014 once groundwater production wells were in place. A summary of AVEK’s historical SWP deliveries to its banking sites is provided in Figure ES-2.

Figure ES-2. 2011–2020 AVEK Historical SWP Deliveries to Groundwater Banking Sites

70,000

60,240 60,000 Total

50,000 Upper Amargosa Creek Recharge Project 40,000 Eastside Water Bank AFY 30,000 27,823 23,384 Westside Water Bank 20,000 16,329 12,831 14,086

10,000 7,213 High Desert Water Bank 371 0 0 0 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020

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Executive Summary

AVEK’s goal is to have enough storage in the groundwater banks so that the agency is prepared to meet demands during three consecutive years of 10% Table A allocations from the SWP. AVEK currently has roughly 90,000 acre-feet (AF) of SWP water stored within its banks for future recovery and is implementing infrastructure projects to expand its capacity to recharge water, recover water, and distribute recovered water. Based on the demand projections presented above, the target groundwater bank storage capacity and annual production capacity are projected in Figure ES-3.

Figure ES-3. Projected AVEK Groundwater Banking Target Sizing

140,000 132,990 126,600 117,450 120,000 115,530

97,260 100,000

80,000 AFY 77,730 or

AF 60,000 42,200 44,330 38,510 39,150 40,000 32,420

20,000 25,910

0 2020 2025 2030 2035 2040 2045

Target Storage Capacity (AF) Target Production Capacity (AFY)

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Water Sources and Uses As shown in Figure ES-4, AVEK’s potable water deliveries consist of either SWP water treated at AVEK water treatment plants, or groundwater that is either recovered from recharge in previous years or part of AVEK’s adjudicated groundwater production rights. In addition, AVEK must acquire new supplies for Los Angeles County Waterworks Districts (LACWD). Each supply is discussed further below.

Figure ES-4. 2011–2020 AVEK Drinking Water Deliveries by Source

Water Treatment Plants From Recovery Sites Total 50,000 44,355 43,016 43,837 45,000 40,858 40,960 39,058 40,000 36,666 34,205 35,000 32,385 9,234 9,162 12,228 30,000 26,998 11,512 7,868

25,000 11,888 44,355 43,837

20,000 10,358 43,016

15,000 31,624 29,896 28,732 26,337 10,000 25,154 20,497

5,000 16,640

0 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020

State Water Project SWP water availability depends on rainfall, snowpack, runoff, reservoir storage, pumping capacity of SWP facilities, and regulatory and environmental mandates on SWP operations. DWR prepares a biennial report to assist SWP contractors and local planners in assessing the availability of supplies from the SWP. DWR’s most recent update was the 2019 State Water Project Delivery Capability Report (DCR) (California Department of Water Resources, 2020). The 2019 DCR includes DWR’s estimates of SWP water supply availability under both existing (2020) and future conditions (2040) for the SWP as a whole and specifically for AVEK. To evaluate SWP supply availability under future conditions, the 2019 DCR included a model study representing hydrologic and sea level rise conditions in 2040. The future condition study used the same model assumptions as the study under existing conditions but reflected changes expected to occur from climate change, specifically, projected temperature and precipitation changes centered around 2035 (2020 to 2049) and a 45 cm sea level rise. For the long-term planning purposes of this UWMP, the long-term average allocations reported for the future conditions study from the 2019 DCR is the most appropriate estimate of future SWP water supply availability. AVEK assumes a straight-line

Antelope Valley-East Kern Water Agency 2020 Urban Water Management Plan May 2021 ES-5 DRAFT Executive Summary reduction in long-term average allocation from 58% in 2020 to 52% in 2040. Allocation in 2045 is assumed to remain at 52%, as shown in Table ES-3.

Table ES-3. SWP Average Yield Projections

2020 2025 2030 2035 2040 2045 Average Table A Allocation (%) 58.0% 56.5% 55.0% 53.5% 52.0% 52.0%

Average Table A Yield (AFY) 84,010 81,840 79,660 77,490 75,320 75,320

DWR’s 2019 DCR indicates that the modeled single dry year SWP water supply allocation is 7% under existing conditions. However, historically, the lowest SWP allocations were 5% in 2014 and 2021 (as of May 2021). DWR’s 2019 DCR indicates that the lowest consecutive five-year period occurred from 1988 to 1992, with an average allocation of 20.3% under the existing conditions. During the recent drought, Table A allocation from 2012 to 2016 averaged 37%.

Groundwater AVEK’s groundwater wells are located within the Antelope Valley Groundwater Basin (Basin). The Basin was adjudicated in 2015 after 15 years of complex proceedings among more than 4,000 parties, including public water suppliers, landowners, small pumpers and non-pumping property owners, and the federal and state governments. The Antelope Valley Area of Adjudication covers approximately 1,390 square miles, or 90% of the groundwater basin. The Judgment determined the Basin is in a state of overdraft, established respective water rights among groundwater producers based on the Basin’s Native Safe Yield, and ordered a ramp-down of production to meet the Native Safe Yield by 2023. The adjudication defined a native safe yield of 82,300 AFY. To achieve sustainable groundwater elevations, groundwater production will be reduced (ramped down) over a seven-year period (2016–2022) to a final production right. Following the adjudication, the Antelope Valley Watermaster was formed to implement the Judgment. The Watermaster is charged with administering the adjudicated water rights and managing the groundwater resources within the adjudicated portion of the Antelope Valley. Within AVEK’s service area, groundwater production rights within the AVEK service area will decrease to 15,634 AFY by 2023, including AVEK’s 3,550 AFY production right. In addition, AVEK and other pumpers receive groundwater pumping rights from imported water return flows equal to the applicable percentage multiplied by the average amount of imported water used by that party within the basin in the preceding five-year period. AVEK received 822 AF of groundwater in 2019 from imported water return flows. In recent years, AVEK has leased a portion of its groundwater productions rights to LACWD for the districts’ use. New Supplemental Water Supply (per LACWD MOU) LACWD is required to acquire new supplemental water supplies for any new growth. Per the memorandum of understanding (MOU) agreement with LACWD, AVEK will acquire the supplies on behalf of LACWD, and AVEK will deliver the water to LACWD along with AVEK’s existing supplies. The supplies can be: (a) water supply originating outside the Basin and imported into the Basin by AVEK in addition to AVEK’s SWP Table A annual allocation; (b) water supply generated by AVEK groundwater production rights; and (c) any other water supply generated through AVEK’s acquisition of any other water right. Since LACWD represents roughly 70% of AVEK retailer sales, new supply volumes equivalent to 70% of new demand are assumed to be added to supplies over time. The new supplemental water supplies are assumed to have greater reliability than SWP Table A supplies based on the mix of supplies.

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Summary of Projected Water Supplies Based on the supplies described above, reasonably available volumes of AVEK water supplies are projected in Table ES-4. In addition, AVEK can supplement supplies by recovering banked SWP water in groundwater or accessing supplies, if available, such as carryover groundwater or SWP water types other than Table A.

Table ES-4. Projected Water Supplies

2025 2030 2035 2040 2045 SWP Table A 81,840 79,660 77,490 75,320 75,320

Groundwater, Production Rights 3,550 3,550 3,550 3,550 3,550

Groundwater, Imported Water Return Flows 800 800 800 800 800

New Supply (per LACWD MOU) 4,890 9,780 12,190 14,760 17,340

TOTAL 91,080 93,790 94,030 94,430 97,010

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Water Supply Reliability Water supply reliability reflects AVEK’s ability to meet the water needs of its customers with water supplies under varying conditions. AVEK’s water reliability goal is to provide a level of regional water reliability that supports customers’ water needs. The foundational strategy of this goal is to develop groundwater banking programs to help increase the reliability of the greater Antelope Valley region’s water supplies by storing excess SWP water during wet periods and recovering it for delivery to customers during dry and high-demand periods or during a disruption in deliveries from the SWP. AVEK evaluated its water supply reliability for normal, single dry, and multiple dry years through 2045 and assessed the drought risk over the next five years. The analysis considered plausible hydrological and regulatory variability, climate conditions, and other factors that affect the Agency’s water supply and demand. Normal Year Total normal year AVEK supplies are shown in Figure ES-5 based on the supply projections discussed above. As shown in the figure, AVEK has sufficient supplies in normal years and could use available supplies to add to groundwater storage for dry periods. For example, SWP water could be recharged when available, or unused groundwater rights could be carried over for use in future years.

Figure ES-5. AVEK Supply and Demand Projections, Normal Year

120,000

97,010 Total AVEK Supplies 100,000 93,790 94,030 94,430 91,080

4,890 9,780 12,190 14,760 17,340 4,350 4,350 80,000 4,350 4,350 4,350

60,000 AFY 57,590 55,210 Total AVEK Demand 50,990 51,880 44,440 40,000 New Supply (per LACWD MOU) 20,000 AVEK Groundwater

AVEK SWP Table A 81,840 79,660 77,490 75,320 75,320 0 2025 2030 2035 2040 2045

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Single Dry Year Single dry year yield for SWP water is based on actual 2014 allocation of 5% (and 2021, as of this writing). Groundwater rights are not impacted by short-term drought conditions, so normal year groundwater yield assumptions are applied. The new supplemental water supplies (per LACWD MOU) are assumed to have greater reliability than SWP Table A supplies based on the mix of supplies. The remainder of demand is met with groundwater in storage. As shown in Figure ES-6, groundwater bank supplies enable AVEK to meet its demands in a single dry year.

Figure ES-6. AVEK Supply and Demand Projections, Single Dry Year

70,000

60,000 57,590 Total AVEK Demand 55,210 50,990 51,880 50,000 44,440 28,660 40,000 28,860 28,100 AVEK Groundwater Bank 29,620 AFY New Supply 30,000 27,960 (per LACWD MOU) AVEK Groundwater

AVEK SWP Table A 17,340 20,000 14,760 9,780 12,190 4,890 10,000 4,350 4,350 4,350 4,350 4,350

7,240 7,240 7,240 7,240 7,240 0 2025 2030 2035 2040 2045

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Executive Summary

Five Consecutive Dry Years For multiple dry years, SWP water availability is based on 1988 to 1992 simulated yield from the 2019 SWP DCR for AVEK, which estimated the following annual Table A allocation:  Year 1 (1988) 12.3%  Year 2 (1989) 32.2%  Year 3 (1990) 13.3%  Year 4 (1991) 25.6%  Year 5 (1992) 18.0% Similar to single dry year, new supplemental water supplies (per LACWD MOU) are assumed to have greater reliability than SWP Table A supplies, groundwater rights are not impacted by an extended drought, and groundwater bank supplies are used to meet remaining demands. Figure ES-7 presents the total volume used from AVEK’s groundwater bank during a multiple-year drought in comparison with the target total storage volume. As shown in the figure, additional groundwater bank supplies would be available if the five-year drought continued.

Figure ES-7. AVEK Groundwater Bank Storage Capacity vs. Use during Five Consecutive Dry Years

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140,000 137,650 131,190 120,000 119,850 122,220 Total Use of Groundwater Bank 100,000 102,680

Target Storage Capacity

AF 80,000

60,000

40,000

20,000 40,740 43,730 45,880 34,230 39,950

0 2025‐2029 2030‐2034 2035‐2039 2040‐2044 2045‐2049

Antelope Valley-East Kern Water Agency 2020 Urban Water Management Plan May 2021 ES-10 DRAFT

Executive Summary

2021–2025 Drought Risk Assessment Water Code requires a Drought Risk Assessment for the upcoming five years (2021 to 2025) based on the five driest years on record. The supply assumptions are similar to the multiple dry year assumptions except that groundwater production rights are still ramping down in 2021 and 2022, so they are higher than final production rights in 2023, as shown in Table ES-5. AVEK currently has roughly 90,000 AF of SWP water stored within its banks for future recovery and is implementing infrastructure projects to expand its capacity to recharge water, recover water, and distribute recovered water. As shown in Figure ES-8, AVEK still would have over 40,000 AF of groundwater remaining in storage at the end of a five-year drought that starts in 2021.

Table ES-5. AVEK Supply Projections for 2021–2025 Drought Risk Assessment SUPPLIES 2021 2022 2023 2024 2025 SWP, Table A 17,850 46,680 19,280 37,040 26,050

AVEK Groundwater 4,530 4,480 4,430 4,380 4,350

New Supply (per LACWD MOU) 980 1,960 2,940 3,920 4,890

SWP from Groundwater Bank 15,700 0 15,940 0 9,150

TOTAL AVEK SUPPLIES 39,060 53,120 42,590 45,340 44,440

Note: Groundwater bank supplies are used to meet remaining demand.

Figure ES-8. 2021–2025 AVEK Drought Reliability Assessment

140,000

120,000 Groundwater Bank Storage (at end of year) 100,000 SWP from Groundwater Bank 74,300 80,000

AF New Supply 74,300 58,360

or 58,360 (per LACWD MOU) 49,210

AFY 60,000 AVEK Groundwater

42,590 43,340 44,440 SWP, Table A 40,000 39,060 40,930

AVEK Demand 20,000

0 2021 2022 2023 2024 2025

Antelope Valley-East Kern Water Agency 2020 Urban Water Management Plan May 2021 ES-11 DRAFT

Executive Summary

2021 Water Shortage Contingency Plan AVEK’s 2021 Water Shortage Contingency Plan (WSCP) is a detailed plan that describes how AVEK intends to respond to foreseeable and unforeseeable water shortages. A water shortage occurs when the water supply is reduced to a level that cannot support typical demand at any given time. The WSCP is used to provide guidance by identifying response actions to allow for efficient management of any water shortage with predictability and accountability. Preparation provides the tools to maintain reliable supplies and reduce the impacts of supply interruptions due to extended drought or catastrophic supply interruptions. The AVEK 2021 WSCP is included as Appendix H in the 2020 UWMP.

Demand Management Measures Demand management is an integral part of sustainably managing water resources in California. Implementation of demand management measures that help lower demands can improve water supply reliability and help meet both state and regional water conservation goals. AVEK has been a leader in water use efficiency for many years and actively collaborates with local and regional agencies and the communities it serves to support innovative programs that drive change. AVEK implements demand management measures as part of its ongoing operations. Chapter 9 of the 2020 UWMP describes AVEK’s efforts as a wholesale water supplier to promote conservation and reduce demands on water supplies.

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URBAN WATER MANAGEMENT PLAN Introduction This chapter provides a brief overview of the Antelope Valley-East Kern Water Agency and the purpose of this 2020 Urban Water Management Plan. It also describes how the Plan is organized and how it relates to other local and regional planning efforts that AVEK is involved in.

This document presents the 2020 Urban Water Management Plan IN THIS SECTION

(UWMP or Plan) for the Antelope Valley-East Kern Water Agency  About Antelope (AVEK or Agency). Valley-East Kern Water Agency AVEK is a wholesale supplier of State Water Project (SWP) water  Purpose of the Plan to the greater Antelope Valley region. SWP water is a secondary water source for AVEK’s customers and is used in lieu of, or in  Plan Organization addition to, pumped groundwater. The greater Antelope Valley is  Relationship to Other Documents and located in the western part of the Mojave Desert, approximately Initiatives 50 miles northeast of Los Angeles, California. The region is a triangle-shaped, topographically closed basin bordered on the southwest by the San Gabriel Mountains, on the northwest by the Tehachapi Mountains, and on the east by a series of hills and buttes that generally follow the Los Angeles/San Bernardino County line. AVEK’s service area encompasses nearly 2,400 square miles in northern Los Angeles and eastern Kern Counties, as well as a small portion of Ventura County. AVEK has played a major role in the Valley’s water system since it was granted a charter by the State Legislature in 1959 and became an SWP contractor in 1962. AVEK currently provides water to 27 retail water agencies and water companies, as well as to agricultural customers. The five largest retailers are shown along with the AVEK service area in Figure 1-1.

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118°58'59"W 117°58'58"W Coordinate System: NAD 1983 StatePlane California V FIPS 0405 Feet Date: 5/16/2021 Introduction Section 1

Urban Water Management Plan Purpose and Overview In 1983, the State of California enacted the Urban Water Management Planning Act (UWMP Act). The law required any urban water supplier providing water for municipal purposes to more than 3,000 customers, or serving more than 3,000 acre-feet per year, to adopt a UWMP every five years, demonstrating water supply reliability under normal as well as drought conditions. The Plan is required to describe and evaluate water deliveries and uses, water supply sources, demand management measures, and water shortage contingency planning. Since the original UWMP Act was passed, it has undergone significant expansion, particularly since AVEK’s previous UWMP was prepared in 2015. Prolonged droughts, groundwater overdraft, regulatory revisions, and changing climatic conditions affect the reliability of each water supplier, as well as the statewide water reliability overseen by the California Department of Water Resources (DWR) and the State Water Resources Control Board. Accordingly, the UWMP Act has grown to address changing conditions, and the current requirements are found in Sections 10610-10656 and 10608 of the California Water Code. DWR provides guidance for urban water suppliers by preparing the UWMP Guidebook 2020 (California Department of Water Resources, 2021), conducting workshops, developing tools, and providing program staff to help water suppliers prepare comprehensive and useful water management plans, implement water conservation programs, and understand the requirements in the California Water Code. Suppliers prepare their own UWMPs in accordance with the requirements and submit them to DWR. DWR then reviews the plans to make sure they have addressed the requirements identified in the California Water Code. The purpose of this UWMP is for AVEK to evaluate long-term resource planning and establish management measures to ensure adequate water supplies are available to meet existing and future demands. The UWMP provides a framework to help water suppliers maintain efficient use of urban water supplies, continue to promote conservation programs and policies, ensure that sufficient water supplies are available for future beneficial use, and provide a mechanism for response during drought conditions or other water supply shortages.

The UWMP is a valuable planning tool used for multiple purposes, including:  Providing a standardized methodology for water utilities to assess their water resource needs and availability.  Serving as a resource to the community and other interested parties regarding water supply and demand, conservation, and other water-related information.  Providing a key source of information for cities and counties when considering approval of proposed new developments and preparing regional long-range planning documents, such as city and county General Plans.  Informing other regional water planning efforts.

California Water Code Section 10632 includes updated requirements for suppliers to prepare a Water Shortage Contingency Plan (WSCP). The WSCP documents a supplier’s plans to manage and mitigate an actual water shortage condition, should one occur because of drought or other impacts on water supplies. In the 2015 UWMP cycle, the WSCP was part of the UWMP. For the 2020 update, the WSCP is required to be a stand-alone document so that it can be updated independently of the UWMP, but it must be referenced in and attached to the 2020 UWMP.

Antelope Valley-East Kern Water Agency 2020 Urban Water Management Plan May 2021 1-3 DRAFT

Introduction Section 1

UWMP Organization This document was prepared in compliance with the California Water Code and the 2020 Guidelines established by DWR and constitutes AVEK’s 2020 UWMP. A UWMP checklist, to ensure compliance of this Plan with the UWMP Act requirements, is provided in Appendix A. In addition, as required by the California Water Code, standardized tables for the reporting and submittal of UWMP data have been prepared and are included in Appendix B. A selection of these tables is also provided in the body of this Plan, as necessary to present supporting data.

The UWMP is organized as follows:  Chapter 1 – Introduction  Chapter 2 – Plan Preparation  Chapter 3 – System Description  Chapter 4 – Water Use Characterization  Chapter 5 – SBX7-7 Baseline and Targets  Chapter 6 – Water Supply Characterization  Chapter 7 – Water Supply Reliability and Drought Risk Assessment  Chapter 8 – Water Shortage Contingency Plan Overview  Chapter 9 – Demand Management Measures  Chapter 10 – Plan Adoption, Submittal, and Implementation  Appendices A. 2020 UWMP DWR Checklist B. UWMP Tables C. Delta Reliance D. Notifications and Notification List E. Adoption Resolutions F. Antelope Valley Groundwater Adjudication G. Antelope Valley Watermaster 2019 Annual Report H. Water Shortage Contingency Plan

UWMPs in Relation to Other Efforts AVEK coordinated with multiple neighboring and stakeholder agencies to prepare this UWMP. The coordination efforts were conducted to (1) inform the agencies of AVEK’s activities, (2) gather high- quality data for use in developing this UWMP, and (3) coordinate planning activities with other related regional plans and initiatives. In addition to the 2020 UWMP, AVEK is involved in several other internal and external planning efforts, and they collaborate with a variety of stakeholders to achieve coordination and consistency between various planning documents locally and regionally.

Antelope Valley-East Kern Water Agency 2020 Urban Water Management Plan May 2021 1-4 DRAFT

Introduction Section 1

Demonstration of Consistency with the Delta Plan for Participants in Covered Actions Under the Sacramento-San Joaquin Delta Reform Act of 2009, state and local public agencies proposing a covered action in the Delta, prior to initiating the implementation of that action, must prepare a written certification of consistency with detailed findings as to whether the covered action is consistent with applicable Delta Plan policies and submit that certification to the Delta Stewardship Council. Anyone may appeal a certification of consistency, and if the Delta Stewardship Council grants the appeal, the covered action may not be implemented until the agency proposing the covered action submits a revised certification of consistency, and either no appeal is filed or the Delta Stewardship Council denies the subsequent appeal. An urban water supplier that anticipates participating in or receiving water from a proposed covered action—such as a multiyear water transfer, conveyance facility, or new diversion that involves transferring water through, exporting water from, or using water in the Delta—should provide information in their 2015 and 2020 UWMPs that can then be used in the covered action process to demonstrate consistency with Delta Plan Policy WR P1, Reduce Reliance on the Delta Through Improved Regional Water Self-Reliance (WR P1). Senate Bill (SB) X7-1, which was signed in 2009, reformed Sacramento-San Joaquin Delta (Delta) policy and governance, including requiring development, adoption, and implementation of a Delta Plan and establishing a statewide policy to reduce reliance on the Delta in meeting California’s future water supply needs, through a statewide strategy of investing in improved regional supplies, conservation, and water use efficiency. DWR does not review this analysis as part of the UWMP approval process; therefore, this information has been prepared as a stand-alone document and is attached as Appendix C. The analysis and documentation provided in the appendix include the elements described in WR P1(c)(1) that need to be included in a water supplier’s UWMP to support a certification of consistency for a future covered action.

Antelope Valley-East Kern Water Agency 2020 Urban Water Management Plan May 2021 1-5 DRAFT

URBAN WATER MANAGEMENT PLAN Plan Preparation This chapter provides information on the processes used for developing the UWMP, including efforts in coordination and outreach.

This Urban Water Management Plan (UWMP or Plan) was IN THIS SECTION prepared following guidance from the California Department of  Plan Preparation Water Resources (DWR) UWMP Guidebook 2020 (Department  Coordination and of Water Resources, 2021) and the 2020 UWMP DWR Checklist Outreach (Appendix A). The 2020 UWMP was prepared in a transparent manner, and the Antelope Valley-East Kern Water Agency (AVEK or Agency) actively engaged stakeholders, cities, counties, water agencies, and the public to both seek and distribute information about water use, supply, and reliability to strengthen the region’s ability to assess and plan for the region’s water future. This chapter provides details regarding AVEK’s UWMP preparation and the coordination and outreach efforts conducted.

Antelope Valley-East Kern Water Agency 2020 Urban Water Management Plan May 2021 2-1 DRAFT

Plan Preparation Section 2

Plan Preparation AVEK prepared this 2020 UWMP in accordance with Water Code Section 10617, which requires water suppliers with 3,000 or more service connections, or those supplying 3,000 acre-feet per year (AFY) or more to prepare a UWMP. Suppliers are required to update UWMPs at least once every five years on or before July 1 in years ending in one and six, incorporating updated and new information from the five years preceding each update. AVEK’s 2020 UWMP was submitted to DWR by July 1, 2021.

Basis for Preparing a Plan AVEK has prepared an individual UWMP as a wholesale agency and is not a member of a Regional UWMP or Regional Alliance. Throughout this report, water volume is represented in units of acre-feet or AFY, unless otherwise noted, and data is presented on a calendar year basis.

Coordination and Outreach AVEK coordinated with multiple neighboring and stakeholder agencies to prepare the 2020 UWMP. The coordinated efforts were conducted to inform the agencies of AVEK’s efforts and activities; gather high-quality data for use in developing this UWMP; and coordinate planning activities with other related regional plans and initiatives. California Water Code Section 10621(b) requires that suppliers notify cities and counties to which they serve water that the UWMP and Water Shortage Contingency Plan (WSCP) are being updated and reviewed. The Water Code specifies that this must be done at least 60 days prior to the public hearing about the updated plan. To fulfill this requirement, AVEK sent letters of notification of preparation of the 2020 UWMP, 2021 WSCP, and Appendix J addendum to the 2015 UWMP to the cities and counties within AVEK’s service area, listed below, 60 days prior to the public hearing.  City of California City  City of Lancaster  City of Palmdale  Kern County  Los Angeles County  Ventura County Copies of the 60-day notification letters are attached as Appendix D. The notifications to cities, counties, and retailers are further discussed in Chapter 10. To fulfill the requirements of Water Code Section 10642 of the Urban Water Management Planning Act (UWMP Act), AVEK made the 2020 UWMP, 2021 WSCP, and Appendix J addendum to the 2015 UWMP available for public review and held a public hearing on June 8, 2021. The public review hearing was noticed on May 25, 2021; the hearing notice is attached as Appendix D. In addition, AVEK maintained a copy of the 2020 UWMP, 2021 WSCP, and Appendix J addendum to the 2015 UWMP in its office prior to the public hearing.

Antelope Valley-East Kern Water Agency 2020 Urban Water Management Plan May 2021 2-2 DRAFT

Plan Preparation Section 2

2.3.1 Wholesale and Retail Coordination AVEK’s service area includes 27 customers, and all were informed of AVEK’s UWMP update and water supply projections from 2020 through 2045 for average, single, and five consecutive dry years.

In compliance with California Water Code 10631, AVEK notified these customers:  Antelope Valley Country Club  Landale MWC  Antelope Valley Water Storage, LLC c/o WDS  Los Angeles County Waterworks Districts  Boron Community Services District (CSD) (LACWD) No. 37 and No. 40  California Department of Parks & Recreation  Mojave Public Utility District (Poppy Reserve)  Palm Ranch Irrigation District  California Water Service Company (Cal  Quartz Hill Water District Water) (Antelope Valley District)  Rancho Vista Development  City of California City  Rio Tinto Minerals (US Borax)  Desert Lake CSD  Rosamond Community Services District  Desert Sage Apartments  Shadow Acres MWC  Edgemont Acres Mutual Water Company  Sunnyside Farms MWC (MWC)  Tejon Ranch Co.  Edwards Air Force Base  Westside Park MWC  El Dorado MWC  White Fence Farms MWC  Granite Construction (Shell Exploration)  White Fence Farms MWC #3  Lake Elizabeth MWC

Copies of the 60-day notification letters are attached as Appendix D.

There are five retail customers within AVEK’s service area that are required to prepare an UWMP, and additional coordination occurred with these agencies:  California Water Service Co. (Antelope Valley  LACWD No. 37 and No. 40 District)  Quartz Hill Water District  City of California City  Rosamond Community Services District

2.3.2 Coordination with Other Agencies and the Community Several years ago, AVEK and 10 additional public agencies representing the broad interests of the greater Antelope Valley region formed a Regional Water Management Group. The 11 agencies signed a Memorandum of Understanding that defines roles and responsibilities to make formal decisions regarding the scope and content of the Antelope Valley Integrated Regional Water Management Plan (IRWMP). Since initial development of the IRWMP in 2007, phased efforts have been advanced to define a meaningful course of action to meet the demands for water within the greater Antelope Valley region and the shared vision within the region. AVEK remains involved in regional water management efforts and most recently participated in the 2019 update to the IRWMP (Antelope Valley Integrated Regional Water Management Group, 2019).

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URBAN WATER MANAGEMENT PLAN System Description This chapter describes the AVEK service area, customers, and land uses, as well as population, demographics, and climate.

Antelope Valley-East Kern Water Agency (AVEK or Agency) is a IN THIS SECTION wholesale supplier of State Water Project (SWP) water to the  AVEK Service Area greater Antelope Valley region. The region is located in the  Service Area western part of the Mojave Desert, approximately 50 miles Climate, Population northeast of Los Angeles. AVEK’s service area encompasses and Land Uses nearly 2,400 square miles in northern Los Angeles and eastern Kern Counties as well as a small portion of Ventura County. AVEK has played a major role in the Valley’s water system since it was granted a charter by the State Legislature in 1959 and became a SWP contractor in 1962. AVEK’s mission is to deliver reliable, sustainable, and high-quality supplemental water to the region in a cost-effective and efficient manner. AVEK’s goals include groundwater basin stewardship, water reliability, and water quality promotion.

Antelope Valley-East Kern Water Agency 2020 Urban Water Management Plan May 2021 3-1 DRAFT

System Description Section 3

General Description In 1962, AVEK signed a water supply contract with the California Department of Water Resources (DWR) for delivery of imported water supplies from the SWP to supplement Antelope Valley region’s groundwater supplies. AVEK has the third-largest allotment of the 29 SWP contractors, with a contractual Table A amount of 144,844 acre-feet per year (AFY). Only the Metropolitan Water District of Southern California (Metropolitan) and Kern County Water Agency receive a larger allotment. Table A water is a reference to the amount of water listed in “Table A” of the contract between the SWP and the contractors and represents the maximum amount of water a contractor may request each year. Table A water is the primary delivery type of imported water AVEK receives; however, additional delivery types (e.g., Article 21 Water and Carryover Water) help to make up AVEK’s full imported water supply. AVEK’s imported water delivery types are further described in Chapter 6. AVEK’s water system is connected to the California Aqueduct at 23 different turnouts. However, only 15 of the turnouts are currently operational. AVEK’s turnouts feed into six separate subsystems that are hydraulically disconnected from each other: Acton; Eastside; Rancho Vista; Rosamond; Quartz Hill; and Willow. Distribution throughout AVEK’s service area is carried out through a system of approximately 184 miles of pipeline. Water travels throughout the system using booster pump stations that pump water from the lower elevations to the higher elevations. AVEK’s pump stations are located at water treatment plants (WTPs) or at customer connections. There are currently 11 existing pumping stations within AVEK’s system. AVEK owns and operates four treatment plants that treat SWP water to drinking water standards from the aqueduct and deliver the treated water into the regional distribution system. The four WTPs and the year they were constructed are: Acton WTP (1991); Eastside WTP (1981); Quartz Hill WTP (1977); and Rosamond WTP (1978). AVEK’s water distribution systems rely on stored water to help equalize fluctuations between supply and demand. In addition, storage is required to provide adequate water supply for emergency or unplanned outages of a major source of supply. Currently, the Agency’s water system has clearwells co-located with each WTP and seven reservoirs that provide storage for the distribution system, five of which are owned and maintained by AVEK and two of which are owned by Los Angeles County Waterworks Districts (LACWD) and maintained by AVEK (Carollo, 2020). In addition, AVEK developed groundwater banking programs to store surplus water available from the SWP during wet periods through groundwater recharge to increase water supply reliability in the greater Antelope Valley. The banking programs include recovery wells to supplement imported water during dry periods, high delivery periods, or during a disruption of SWP deliveries. Currently, AVEK’s groundwater banks include the Westside Water Bank (started operations in 2010), Eastside Water Bank (started operations in 2016), Upper Amargosa Creek Recharge Project (started operations in 2019), and, most recently the High Desert Water Bank (currently in development). AVEK has made many improvements to its water system since initially being constructed in the 1970s to allow for better distribution of water through system interconnections and expansions. The South North Intertie Pipeline and Pump Station/Turnout Project (SNIP) Phase 1 was constructed in 2011 to connect the existing Rosamond WTP and the Quartz Hill WTP by moving water through LACWD pipelines. SNIP also provides flexibility in the method of return of water banked in the Westside Water Bank (direct delivery or transfer). SNIP Phase 2 is currently in design. Other previous facility improvements include the Parallel South Feeder and the addition of 9 million gallons of storage at the Quartz Hill WTP. The Agency’s major facilities are shown in Figure 3-1. AVEK is currently developing a new storage program, the High Desert Water Bank, which is a partnership between AVEK and Metropolitan to increase water supply reliability by storing excess Metropolitan SWP supply in the Antelope Valley Groundwater Basin for use during periods of low SWP allocation. As the project expands and additional phases are constructed, AVEK will have dedicated capacity and the ability to recover stored imported water from the groundwater basin and pump the recovered water into the East Branch of the California Aqueduct for downstream deliveries to AVEK’s existing water treatment facilities. Antelope Valley-East Kern Water Agency 2020 Urban Water Management Plan May 2021 3-2 DRAFT

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! ! System Description Section 3

Service Area Climate AVEK’s service area is located in the western part of the Mojave Desert within the greater Antelope Valley. The region’s elevation ranges from approximately 2,300 feet to 3,500 feet above sea level. Vegetation native to the greater Antelope Valley region is typical of the high desert and includes Joshua trees, saltbush, mesquite, sagebrush, and creosote bush. The climate is characterized by hot summer days, cool summer nights, cool winter days, and cool winter nights. Typical of a semiarid region, mean daily summer temperatures range from 64 degrees Fahrenheit (°F) to 96°F, and mean daily winter temperatures range from 35°F to 60°F (Antelope Valley Integrated Regional Water Management Group, 2019). Summer temperatures can reach 112°F, while winter temperatures can drop to about 10°F. Typical annual rainfall is 4 to 6 inches. Most rainfall occurs between December and March, with little to no precipitation falling in summer months. The perimeter of the greater Antelope Valley includes low brush-covered hills transitioning into the Tehachapi Mountains to the west and the San Gabriel Mountains to the south. Surface water drainage channels and courses are only active during times of runoff due to precipitation. The water tables are well below the levels needed to sustain year-round flowing streams. The area is known for its daily winds, primarily from the west. Table 3-1 presents the average rates of evapotranspiration (ETo), temperature, and precipitation in the service area.

Table 3-1. Precipitation, Evapotranspiration, and Temperature in AVEK Service Area

JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC AVG Average 1.0 0.9 1.1 0.3 0.2 0.0 0.1 0.2 0.2 0.2 0.4 0.8 0.4 Precipitation (inches) Average 2.3 3.1 4.9 6.5 8.2 9.2 9.8 8.9 6.5 4.6 2.9 2.0 5.8 ETo (inches) Average 43.3 46.2 51.2 57.0 64.3 73.2 78.4 78.1 71.3 59.8 49.8 42.2 59.8 Air Temp (°F) Source: California Irrigation Management Information System (CIMIS), Station 197 Palmdale, (period of record is from April 2005 through December 2020) http://wwwcimis.water.ga.gov/cimis/data

Climate change and the potential impacts within the Agency’s service area are discussed in Section 4.2.4, climate change considerations.

Service Area Population and Demographics AVEK provides service to incorporated and unincorporated areas of the greater Antelope Valley. The current and projected population and demographic projections for AVEK’s service area (Table 3-2 and Table 3-3, respectively) were based on population projections from the Southern California Association of Governments (SCAG) for Los Angeles and Ventura Counties, and the Kern Council of Governments (KCOG). The SCAG projection data was last updated in December 2019 and is the projection modeling information that SCAG used in the 2020 Connect SoCal Regional Transportation Plan (Southern California Association of Governments, 2020). Population projections were calculated based on the SCAG 2019 regional growth forecast for the transportation analysis zones overlying AVEK service area.1 The estimates were developed using SCAG’s traffic analysis zones (TAZs), which were clipped to AVEK’s service area boundary in ArcGIS. TAZs that were partially outside the service area were estimated based on the percentage of the area that lies within AVEK’s service area. SCAG’s 2019

1 The analysis was performed by WSC based upon modeling information originally developed by SCAG. SCAG is not responsible for how the model is applied or for any changes to the model scripts, model parameters, or model input data. The resulting modeling data does not necessarily reflect the official views or policies of SCAG. SCAG shall not be held responsible for the modeling results or the content of the documentation. Antelope Valley-East Kern Water Agency 2020 Urban Water Management Plan May 2021 3-4 DRAFT

System Description Section 3

model data has estimates for 2016 (historical estimate), 2020, 2035, and 2045. Intermediate values are linear interpolations between the given SCAG values. SCAG prepared preliminary demographic forecast estimates for each TAZ in 2017 for the 2020 Connect SoCal Plan. Between 2017 and 2019, SCAG met with each jurisdiction to review the demographic forecasts. This review process incorporated feedback from each jurisdiction, including land use planning departments, to help align the demographic forecasts with current land use and anticipated land use changes. The KCOG population projection data is from the KCOG General Land Use Plan (Kern County Counil of Governments, 2018) (KCOG, 2018). Similar to SCAG, the KCOG estimates were developed using KCOG’s TAZs. The TAZs were clipped to AVEK’s service area boundary in ArcGIS, and TAZs that were partially outside the service area were estimated based on the percentage of the area that lies within AVEK’s service area. KCOG data is projected for 2020, 2035, and 2042. Similar to SCAG, linear interpolation was applied to intermediate values (2025, 2030, and 2040) and extrapolation for 2045. The combined projections result in an average annual growth rate of 1.33% with a high growth rate initially (2020–2025) and lower rates at the end of the projection (2040–2045).

Table 3-2. Current and Projected Population (DWR UWMP Table 3-1W)

POPULATION SERVED 2020 2025 2030 2035 2040 2045 Los Angeles and Ventura Counties 270,615 288,578 306,542 324,505 342,229 359,953

Kern County 49,956 56,757 63,558 70,359 78,738 87,118

TOTAL 320,571 345,335 370,100 394,864 420,967 447,071

Notes: 1. Data for Los Angeles and Ventura Counties from SCAG 2020 Connect SoCal Regional Transportation Plan (SCAG, 2020) 2. Data for Kern County from KCOG General Land Use Plan (KCOG, 2018a).

Table 3-3. Current and Projected Households and Employment

2020 2025 2030 2035 2040 2045

HOUSEHOLDS

Los Angeles and Ventura Counties 85,305 94,696 104,088 113,479 121,487 129,495

Kern County 16,380 18,679 20,978 23,277 26,051 28,825

TOTAL 101,685 113,375 125,066 136,756 147,538 158,320

EMPLOYMENT

Los Angeles and Ventura Counties 88,296 93,530 98,764 103,998 110,167 116,335

Kern County 17,745 20,342 22,940 25,537 28,496 31,456

TOTAL 106,041 113,872 121,704 129,535 138,663 147,791

Notes: 1. Data for Los Angeles and Ventura Counties from SCAG 2020 Connect SoCal Regional Transportation Plan (SCAG, 2020) 2. Data for Kern County from KCOG General Land Use Plan (KCOG, 2018).

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URBAN WATER MANAGEMENT PLAN Water Use Characterization This chapter summarizes AVEK’s past, current, and projected water demands through 2045.

Antelope Valley-East Kern Water Agency (AVEK or Agency) IN THIS SECTION delivers treated water and untreated water to customers within  Past Water Use its service area. All connections are metered and are cross-  Current Water Use checked with California Department of Water Resources (DWR) State Water Project (SWP) delivery records. In addition, AVEK  Projected Water Use delivers untreated water for recharge of the local groundwater basin and conducts exchanges or transfers for delivery of a portion of its SWP allocation to agencies with a short-term need for additional water supplies. As an SWP contractor, AVEK provides a supplemental imported water supply from the SWP to retailers in the greater Antelope Valley region. This is a secondary water source for these suppliers and is used by these entities in lieu of, or in addition to, pumped groundwater. Therefore, AVEK must first project total demand in the AVEK service area, along with projected utilization of local supplies, to estimate demands on AVEK supplies. The primary local supply is groundwater, but several agencies are investing in recycled water and recharge projects to diversify their water supplies. This chapter describes recent demands in the AVEK service area and projections through 2045 for water demand in the AVEK service area, local supplies, and AVEK demands.

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Past and Current Water Use As a wholesale water supplier, AVEK reports the sale of water to other agencies; the retail water supplier is responsible for reporting the uses of their water supply by water sector. Water use sectors relevant to AVEK include sales to other agencies, groundwater recharge (groundwater banking), losses, and transfers/exchanges. Water delivery data for 2020 is summarized in Table 4-1 and presented along with 2011–2019 deliveries in Figure ES-1.

Table 4-1. Actual Demands for Water (DWR 4-1W) (Acre-Feet per Year)

CUSTOMER OR USE LEVEL OF TREATMENT WHEN DELIVERED 2020 VOLUME Los Angeles County Waterworks Districts Treated Water 32,847

Quartz Hill Water District Treated Water 2,533

Rio Tinto Minerals / US Borax Treated Water 1,503

Edwards Air Force Base Treated Water 1,465

Other M&I Customers (19 Customers) Treated Water 2,095

Untreated Water Deliveries (4 Customers) Untreated Water 837

Transfers to Other Agencies Untreated Water 11,286

Groundwater Recharge Untreated Water 7,213

Losses Treated and Untreated Water 457

TOTAL: 60,234

Source: AVEK, 2020 LATIS data

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Figure 4-1. 2011–2020 AVEK Deliveries by Type

160,000 Untreated Water to Other Locations Untreated Water to Recharge Sites 140,000 Treated Water Deliveries

120,000 51,028

100,000 49,807 35,887 80,000 AFY 36,860 26,116 60,240 60,000 19,640 23,384 27,823 12,061 12,831 6,814 16,329 371 14,086 7,213 40,000 12,480

20,000 44,355 43,016 43,837 40,858 40,960 36,666 34,205 39,058 32,386 26,998

0 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020

As shown in Figure 4-1, treated water deliveries to AVEK retailers were relatively consistent compared with deliveries to recharge sites and other locations. Treated water demands have increased slightly since 2017 but have not returned to the levels observed prior to 2014, following severe drought restrictions. Recharge water deliveries have varied based on water availability, as evidenced by the high recharge volume in 2017 that coincided with high SWP allocations. Future use of untreated water for recharge is discussed further in Section 6.1.2. Similarly, yearly deliveries to other locations vary substantially and are primarily driven by the extent of exchanges or transfers conducted in those years. Exchanges and transfers are not explicitly projected in this UWMP because they are opportunistic agreements made by willing parties dependent on each party’s needs, and they are the lowest priority use of AVEK’s supplies. The remainder of this chapter focuses on treated water demand projections.

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Water Use Characterization Section 4

Projected Water Use AVEK developed a Supply and Demand Model (“the model”) in Microsoft Excel to compare future supply and demand conditions under multiple supply and demand scenarios. Scenario analysis allows AVEK to compare the benefits (and costs) of different long-term water resources conditions and strategies. The model is comprised of supply and demand variables, which are combined to form scenarios with different supply and demand assumptions.

The following demand variables were considered:

Population Growth Active Conservation Projects the number of new water users in the service area, based on planning agency Water saved as a direct result of programs and projections and historical growth rates. practices directly funded by a water utility.

Per Capita Demand Rebound Climate Change The extent that per capita demand, measured Climate models disagree on average annual as gallons per capita per day (GPCD), is precipitation projections but agree on other estimated to increase from spring 2016, which hydrologic metrics relevant to water resources was the last year severe water use restrictions management, including increased were in place by AVEK retailers. This variable evapotranspiration, which would increase projects the “new normal” demand for existing irrigation demands (Persad, 2020) (Partida, customers. 2020).

Passive Conservation Water savings resulting from plumbing codes and other institutionalized water efficiency measures.

Also, as a SWP contractor, AVEK provides a supplemental imported water supply to retailers in the greater Antelope Valley region, which is a secondary water source for these suppliers and is used by these entities in addition to pumped groundwater; therefore, local supply variables were also considered:

Groundwater Recycled water Includes pumping at production rights, as well Includes with and without planned recycled as pumping below the production rights. water use by retailers

For the 2020 UWMP, AVEK made one assumption for each of the variables listed above. Each variable is discussed on the following page, along with the assumption used for this UWMP.

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4.2.1 Population Growth Population growth projections are based on projections from Southern California Association of Governments (SCAG) for Los Angeles and Ventura Counties and Kern County Council of Governments (KCOG) and were presented in Section 3.3. The combined result is an average annual growth rate of 1.33%, with a high growth rate initially (2020–2025) and lower rates at the end (2040–2045). AVEK considered both higher and lower growth rate scenarios but applies the projections from Section 3.3 for the UWMP demand projections.

4.2.2 Per Capita Demand Rebound Senate Bill (SB) X7-7 mandated reduction of per capita water demand by 20% by 2020. As a wholesaler, AVEK does not have a 2020 target, but every retailer that prepares a UWMP must have developed a 2020 target for their 2015 UWMP and must have been reporting water use monthly to the State since June 2014. Five of AVEK’s retailers—California Water Service Co., City of California City, Los Angeles County Waterworks District (LACWD), Quartz Hill Water District (QHWD), and Rosamond Community Service District (RCSD)—must prepare UWMPs and report water use to the State; they represent roughly 90% of AVEK demand and 80% of population in the AVEK service area.

4.2.2.1 Historical Per Capita Demand Table 4-2 estimates per capita water demand for all AVEK customers (using AVEK billing and production data), while

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Figure 4-2 includes only AVEK customers that must submit a UWMP (using required monthly water use reporting to the State Water Resources Control Board [SWRCB]). As shown in the table and figure, per capita water demand in 2020 was higher than from 2015 to 2017. There was a drop in use in 2019 that may have been caused by higher than average precipitation—the area received over 7.0 inches of precipitation, while the other years from 2015 to 2020 received from 3.6 to 4.0 inches.

Table 4-2. 2016–2020 AVEK Service Area GPCD – All Customers

2016 2017 2018 2019 2020 Treated Water Deliveries by AVEK (AF) 36,666 34,205 39,058 40,858 40,960

Groundwater Pumped by Customers (AF) 24,553 26,139 26,007 20,211 20,556

TOTAL USE (AF) 61,219 60,344 65,065 61,068 61,516

Population Estimate 310,407 312,911 315,415 317,951 320,571

PER CAPITA WATER DEMAND (GPCD) 176 172 184 171 171

Source: Treated water deliveries from AVEK billing records; Groundwater pumping from annual Watermaster reports; Population estimates from SCAG and KCOG.

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Figure 4-2. 2015–2020 AVEK Retailers with UWMPs GPCD for Trailing 12 Months

250

240

230 2020 GPCD Target (Weighted Average) 220 12‐Month Trailing GPCD (Weighted Average) 210

200 GPCD

190

180 Actual 2015 GPCD 170 (Weighted Average)

160

150

Source: SWRCB Monthly Water Conservation and Production Reports1 Note: The figure includes only retailers that are required to submit UWMPs, which excludes roughly 10% of demand and 20% of population in the AVEK service area. Values presented are the average from each retailer weighted by their population.

4.2.2.2 Demand Rebound Estimates AVEK considered a range of potential post-drought rebound scenarios for unit water demands, including unit demands for existing connections staying at the existing rate (roughly 185 GPCD) and unit demands increasing to the 2020 GPCD target for AVEK’s retailers that submit UWMPs (roughly 230 GPCD). For the UWMP, AVEK assumed a continued post-drought unit demand rebound to 205 GPCD by 2030, which represents 90% of the weighted average 2020 GPCD target for AVEK retailers that submit an UWMP. However, AVEK intends to monitor monthly reporting by its customers to track trends in unit water demands and plans to adapt its projections based on this and other available information. AVEK assumed 150 GPCD for new development, based on it being more efficient than existing development.

1 https://www.waterboards.ca.gov/water_issues/programs/conservation_portal/conservation_reporting.html Antelope Valley-East Kern Water Agency 2020 Urban Water Management Plan May 2021 4-8 DRAFT

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4.2.3 Passive and Active Conservation Future demands are dependent on passive conservation, active conservation, and customer behavior. Active and passive conservation will reduce unit demand factors over time, while customer behavior could cause increased use (e.g., longer irrigation cycles) or decreased use (e.g., shorter irrigation cycles). Active conservation covers water saved as a direct result of programs and practices directly funded by a water utility, while passive conservation covers water savings resulting from plumbing codes and other institutionalized water efficiency measures. The price of water also impacts customers’ water use, where increased water prices cause decreased water use. For existing connections, unit demand factors will decrease slowly due to passive conservation and changes in customer water use patterns. Future connections are projected to be much more water efficient than existing connections due to California Plumbing Code requirements.2 Unit demand factors for future connections will decrease due to passive conservation at a slower rate than existing connections because future connections will start with the latest plumbing code requirements. Demand projections must account for conservation that may be required to meet the 2018 “Conservation as a California Way of Life” legislative mandates. Following the recent California drought, DWR and SWRCB established a conservation framework centered on “Making Water Conservation a California Way of Life” to help the State better prepare for droughts and climate change by establishing statewide water efficiency standards and incentivizing recycled water (California Department of Water Resources, November 2018). The resulting legislation of Senate Bill (SB) 606 and Assembly Bill (AB) 1668 (signed on May 31, 2018), along with future regulations, will have impacts on water providers over the coming years, requiring indoor, outdoor, and commercial, industrial, and institutional water use goals; water loss standards; annual water budgets; and documented preparation for long-term water shortages. SB 606/AB 1668 requires the SWRCB to adopt urban efficiency standards for indoor use, outdoor use, water loss, variances, and incentives by June 30, 2022. Following the adoption of urban water use objectives in 2022, retailers will first have to report actual water use compared to objectives in 2024, and they must meet the objectives by 2027. Therefore, AVEK will see the potential impact on its customers’ water use within the next decade. AVEK considered several conservation scenarios, ranging from passive conservation only to high active conservation. To be conservative for the UWMP, AVEK is including passive conservation only in the demand projections, assuming a reduction of 0.2% per year (or 5% over 25 years) for existing connections. However, AVEK intends to work with its customers to understand the potential implications of meeting new urban efficiency standards, and plans to adapt its projections based on this and other available information once annual water use reporting starts in 2023.

4.2.4 Climate Change Climate change analysis is an area of continued evolution in terms of methods, tools, forecasted datasets, and the predictions of greenhouse gas concentrations in the atmosphere. While continued warming can be expected, the extent to which climate change will impact other hydroclimatic elements such as precipitation is uncertain. Precipitation patterns are spatially and temporally more complex than warming patterns, and there is more uncertainty among these predictions, with some models showing the state becoming wetter and others showing the state becoming drier. Notably, a scenario with increased precipitation could result in more volatile precipitation patterns in which drought frequency and duration increases. Warming temperatures also increase evaporation from reservoirs and moisture loss from soils, resulting in reductions in water supply.

2 http://epubs.iapmo.org/2019/CPC/index.html Antelope Valley-East Kern Water Agency 2020 Urban Water Management Plan May 2021 4-9 DRAFT

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DWR developed a climate change resource guide to support climate change analysis for development of groundwater sustainability plans under the Sustainable Groundwater Management Act (SGMA) (California Department of Water Resources, 2018), including a SGMA Data Viewer website.3 The website includes precipitation and evapotranspiration change estimates for grids across the State for 2030 and 2070. The 2030 values were used for the UWMP, since they are roughly the midpoint of the planning period. By 2030, precipitation is projected to decrease by 3% and evapotranspiration is projected to increase by 4%, which roughly equates to a net irrigation demand increase of 7%. Increased evapotranspiration would increase irrigation demands. AVEK does not have a reliable estimate for the portion of total demand attributed to irrigation because its supply is one of several used by its customers. Reviewing retailer monthly demand records submitted to the SWRCB,4 irrigation demands appear to be roughly 50% of total demand based on the “minimum month” method (which assumes the lowest month of water use is all indoor use, and the same indoor use is assumed year- round). Based on this assumption, increased evapotranspiration from climate change would increase demand by 3.5%—or about 3,000 acre-feet per year (AFY) over the next 25 years—compared with an over 40% increase in demand from population growth and unit demand rebound. For this UWMP, increased evapotranspiration is not explicitly included in the demand projections contained herein, because assumptions for the other variables discussed above (growth, unit demand, and conservation) have a larger impact on the demand projections, and demand impacts from climate change are within the margin of error for the projections.

4.2.5 Groundwater As detailed in Section 6.3, a Stipulated Judgment (“Judgment”) was approved in 2015 for the Antelope Valley Groundwater Adjudication, and it governs most groundwater pumping in the AVEK service area. The Judgement stipulated production rights to each party, and other methods to access additional groundwater rights, such as from imported water return flows. AVEK’s customers have 12,084 AFY of production rights and have received roughly 12,000 AFY of return flow rights since 2016. Pumping by AVEK customers is shown in Table 4-2. For the UWMP local supply projections, each customer is assumed to pump their full production rights and imported water return flows each year.

4.2.6 Recycled Water AVEK’s retailers have projected an increased use of recycled water to offset potable use, but to date little progress has been made implementing recycled water projects within AVEK’s service area. In its 2020 UWMP, LACWD is projecting increased recycled water use, but the use would not offset potable water. For the UWMP, AVEK assumes no recycled water will be developed that offsets projected water use through 2045.

4.2.7 Distribution System Water Losses Wholesale Suppliers do not have to perform water loss audits and are not required to report this information in their 2020 UWMP. However, AVEK audits its system losses monthly as a part of its normal billing procedures. Pipelines are driven regularly as a part of water sample runs, during which personnel will note leaks if observed. As shown in Table 4-1, 2020 losses represented roughly 1% of supplies delivered within the AVEK service area. The long-term average losses are 2% to 3%, so this value is applied to demand projections. Also, losses are already included in the unit demand estimates

3 https://sgma.water.ca.gov/webgis/?appid=SGMADataViewer 4 https://www.waterboards.ca.gov/water_issues/programs/conservation_portal/conservation_reporting.html Antelope Valley-East Kern Water Agency 2020 Urban Water Management Plan May 2021 4-10 DRAFT

Water Use Characterization Section 4

since they are based on water production (versus customer meters), so a separate line item for losses is not included in the demand projections.

4.2.8 AVEK Demand Projections Based on the assumptions described above, AVEK estimated total service area demand projections and net demand on AVEK projections through 2045 is shown in Table 4-3.

Table 4-3. 2025–2045 AVEK Demand Projections (AFY)

2025 2030 2035 2040 2045

TOTAL AVEK SERVICE AREA DEMAND 73,420 80,400 83,850 87,520 91,200

Non-AVEK Supplies

Groundwater, Non-AVEK Production Rights 12,080 12,080 12,080 12,080 12,080

Groundwater, Non-AVEK Return Flows 16,900 17,330 19,890 20,230 21,530

NON-AVEK SUPPLIES TOTAL 28,980 29,410 31,970 32,310 33,610

NET AVEK SERVICE AREA DEMAND 44,440 50,990 51,880 55,210 57,590

4.2.9 Characteristic Five-Year Water Use In Chapter 7, AVEK’s supplies for the next five years are compared to its demands for the next five years as part of a five-year drought risk assessment. The demand projections, shown in Table 4-4, are supposed to be reported without drought conditions (also known as “unconstrained demand”), so they do not account for potential water shortage measures that AVEK or its customers could enact if an extended drought emerges from recent dry water years.

Table 4-4. 2021–2025 AVEK Demand Projections (AFY)

2021 2022 2023 2024 2025

TOTAL AVEK SERVICE AREA DEMAND 67,830 69,230 70,630 72,030 73,420

Non-AVEK Supplies

Groundwater, Non-AVEK Production Rights 14,060 13,070 12,080 12,080 12,080

Groundwater, Non-AVEK Return Flows 14,710 15,230 15,960 16,610 16,900

NON-AVEK SUPPLIES TOTAL 28,770 28,300 28,040 28,690 28,980

NET AVEK SERVICE AREA DEMAND 39,060 40,930 42,590 43,340 44,440

Source: Note that groundwater production rights ramp down through 2023 and then stay the same after 2023.

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URBAN WATER MANAGEMENT PLAN SBX7-7 Baseline, Targets and 2020 Compliance With the adoption of the Water Conservation Act of 2009, also known as SBX7-7, California is required to reduce urban per capita water use by 20% by the year 2020. To achieve this statewide objective, each retailer was required to develop an urban water use target to help the State collectively achieve a 20% reduction.

As a wholesale supplier, Antelope Valley-East Kern Water IN THIS SECTION

Agency (AVEK) is not required to calculate baseline, targets, or  SBX7-7 compliance gallons per capita per day; therefore, this section is not required. Measures, programs, and policies that AVEK has adopted to help the retail water suppliers within its service area to achieve their SBX7-7 water use reduction targets are discussed in Chapter 9 (Demand Management Measures). Retail water suppliers within AVEK’s service area that are required to prepare and submit an Urban Water Management Plan will include their baselines, targets, and 2020 compliance in their individual Plans. AVEK will continue to work with its retail water suppliers to implement demand management measures (discussed in Chapter 9) to help them achieve their 2020 targets.

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URBAN WATER MANAGEMENT PLAN Water Supply Characterization This section summarizes AVEK’s water supplies and provides the basis for normal, single year, and multiple dry year supply reliability.

The Antelope Valley-East Kern Water Agency (AVEK or IN THIS SECTION

Agency) provides treated (drinking) water and untreated (raw)  State Water Project water to a variety of customers in the greater Antelope Valley,  Exchanges and including municipal water, agricultural water, private companies, Transfers and individual agricultural customers. AVEK primarily supplies  Groundwater imported water from the State Water Project (SWP); however, it  Supply also supplies local groundwater and banked SWP supplies. Characterization AVEK’s mission is to deliver reliable, sustainable, and high-  Energy Intensity quality supplemental water to the region in a cost-effective and efficient manner. AVEK’s water reliability goal is to provide a level of regional water reliability that supports customers’ water needs. The foundational strategy of this goal is developing groundwater banking programs to help increase the reliability of the Antelope Valley region’s water supplies by storing excess SWP water during wet periods and recovering it for delivery to customers during dry and high-demand periods or during a disruption in deliveries from the SWP. To maximize the use of its SWP supplies, AVEK has developed a water banking program and entered into various water transfer and exchange programs with other SWP contractors. In addition to SWP supplies, AVEK also has adjudicated groundwater production rights, which are available to help meet water demands in the region. Information regarding AVEK’s imported water and groundwater supplies is detailed in this chapter.

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Water Supply Characterization Section 6

As shown in Figure 6-1, AVEK’s potable water deliveries consist of either SWP water treated at AVEK water treatment plants, or groundwater that is recovered from SWP water previously recharged or part of AVEK’s production rights. And, as shown in Table 6-1, AVEK also delivers raw (untreated) SWP water to customers for recharge locally or for transfer or exchange outside of the AVEK service area.

Figure 6-1. 2011–2020 AVEK Drinking Water Deliveries by Source

Water Treatment Plants From Recovery Sites Total 50,000 44,355 43,016 43,837 45,000 40,858 40,960 39,058 40,000 36,666 34,205 35,000 32,385 9,234 9,162 12,228 30,000 26,998 11,512 7,868

25,000 11,888 44,355 43,837

20,000 10,358 43,016

15,000 31,624 29,896 28,732 26,337 10,000 25,154 20,497

5,000 16,640

0 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020

Table 6-1. California Department of Water Resources (DWR) 6-8W Actual Water Supplies (DWR 6-8W)

ADDITIONAL DETAIL ON WATER SUPPLY 2020 VOLUME (AFY) Treated Water to Retailers 28,732

Untreated Water to Retailers 775

Untreated Water to Groundwater Bank 7,213

Treated Water from Groundwater Bank 12,228

Untreated Water, Transfer / Exchanges 11,286

TOTAL: 60,234

The following sections further describe each of AVEK’s existing and potential water supplies.

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State Water Project AVEK is a wholesale supplier of SWP water from the California Aqueduct. AVEK has the third-largest allotment of the 29 SWP contractors with a contractual Table A amount of 144,844 acre-feet per year (AFY). Table A water is a reference to the amount of water listed in “Table A” of the contract between the SWP and the contractors, representing the maximum amount of water a contractor may request each year. Table A water is the primary delivery type of imported water AVEK receives; however, additional delivery types help to make up AVEK’s full imported water supply. As listed below and shown in Figure 6-2, AVEK uses a variety of SWP water types.  SWP Table A water: Once the total amount of water to be delivered is determined for the year, all available water is allocated in proportion to each contractor’s annual maximum SWP Table A amount.  SWP Article 21 water: Water that SWP contractors may receive on a short-term basis in addition to their Table A water, if requested. It is predominantly available in wet years.  SWP carryover water: Water that is allocated to an SWP contractor and approved for delivery to that contractor each year, but not used by the end of the year. Instead of being delivered to the contractor, the water is stored in San Luis Reservoir, when space is available, for the contractor to use in the following year. Carryover water credit is lost when the reservoir storage space is full.  SWP turnback pool water: SWP contractors may offer a portion of their Table A water that has been allocated in the current year and exceeds their needs to a “turnback pool,” where another contractor may purchase it.  Other SWP water: Water from negotiated agreements with other SWP contractors.  Other non-SWP water: Water from negotiated agreements with non-SWP contractors that is delivered through SWP.

Figure 6-2. 2011–2020 AVEK SWP Deliveries by Type of Water

160,000 Total SWP 137,666 140,000 Deliveries / 116,207 120,000 95,334 100,000 94,046 Non‐SWP Other SWP 80,000 72,341 AFY Turnback 58,879 60,000 51,022 48,006 Carryover Article 21 40,000 29,120 18,673 Table A 20,000

0 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 Calendar Year

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As shown in Figure 6-3, in addition to delivering SWP water to customers, AVEK optimizes the use of available SWP water through recharge for future use or in deliveries to other SWP locations as exchanges or transfers, which are discussed in Section 6.2.

Figure 6-3. 2011–2020 AVEK SWP Deliveries by Location 160,000 Total SWP 137,605 Deliveries / 140,000 Transfers

116,207 120,000 51,028

100,000 94,046 95,334 49,807 Other SWP Locations 80,000 72,341 36,860 35,887 Recharge (Banking) 58,879 Customer Deliveries 60,000 51,022 26,116 23,384 60,240 48,006 12,831 6,814 19,640 371 27,823 40,000 12,061 29,120 16,329 14,086 7,213 18,673 12,480 20,000 44,355 43,016 43,837 31,624 25,154 26,337 29,896 28,732 20,497 16,640 0 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020

6.1.1 SWP Water Supply Estimates The water supply availability for delivery by the SWP depends on rainfall, snowpack, runoff, reservoir storage, pumping capacity of SWP facilities, and regulatory and environmental mandates on SWP operations. DWR prepares a biennial report to assist SWP contractors and local planners in assessing the availability of supplies from the SWP. DWR issued its most recent update, the 2019 SWP Delivery Capability Report (DCR) (California Department of Water Resources, August 2020). In this update, DWR provides SWP supply estimates for SWP contractors to use in their planning efforts, including for use in their 2020 UWMPs. The 2019 DCR includes DWR’s estimates of SWP water supply availability under both existing (2020) and future (2040) conditions for the SWP as a whole and specifically for AVEK. DWR’s estimates of SWP deliveries are based on a computer model that simulates monthly operations of the SWP and Central Valley Project systems. Key inputs to the model include the facilities included in the system, hydrologic inflows to the system, regulatory and operational constraints on system operations, and contractor demands for SWP water. In conducting its model studies, DWR must make assumptions regarding each of these key inputs. In the 2019 DCR for its model study under existing conditions, DWR assumed: existing facilities; hydrologic inflows to the model based on 82 years of historical inflows (1922 through 2003); current Antelope Valley-East Kern Water Agency 2020 Urban Water Management Plan May 2021 6-4 DRAFT

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regulatory and operational constraints, including 2018 COA Amendment, 2019 biological opinions, and 2020 Incidental Take Permit; and contractor demands at maximum Table A amounts. The long-term average allocation reported in the 2019 DCR for the existing conditions study provides appropriate estimates of the SWP water supply availability under current conditions. To evaluate SWP supply availability under future conditions, the 2019 DCR included a model study representing hydrologic and sea level rise conditions by 2040. The future condition study used all of the same model assumptions as the study under existing conditions, but reflected changes expected to occur from climate change, specifically projected temperature and precipitation changes centered around 2035 (2020 to 2049) and a 45 centimeter sea level rise. For the long-term planning purposes of this UWMP, the long-term average allocations reported for the future conditions study from 2019 DCR is the most appropriate estimate of future SWP water supply availability. AVEK assumes a straight-line reduction in long-term average allocation from 58% in 2020 to 52% in 2040. 2045 is assumed to remain at 52%, as shown in Table ES-3.

Table 6-2. SWP Average Yield Projections

2020 2025 2030 2035 2040 2045 Average Table A Allocation (%) 58.0% 56.5% 55.0% 53.5% 52.0% 52.0%

Average Table A Yield (AFY) 84,010 81,840 79,660 77,490 75,320 75,320

DWR’s 2019 DCR indicates that the modeled single dry year SWP water supply allocation is 7% under existing conditions. Historically, however, the lowest SWP allocations were 5% in 2014 and 2021 (as of May 2021). DWR’s 2019 DCR indicates that the lowest consecutive five-year period occurred from 1988 to 1992, with an average allocation of 20.3% under the existing conditions. During the recent drought, Table A allocation from 2012 to 2016 averaged 37%. AVEK’s SWP projections for single dry year and multiple dry years is presented in Table 6-3.

Table 6-3. Table A Deliveries in Selected Drought Conditions

DROUGHT CONDITION TABLE A ALLOCATION (%) TABLE A ALLOCATION (AF) SINGLE DRY YEAR

2014 5.0% 7,242

MULTIPLE DRY YEARS (1988-1992)

YEAR 1 (1988) 12.3% 17,854

YEAR 2 (1989) 32.2% 46,677

YEAR 3 (1990) 13.3% 19,276

YEAR 4 (1991) 25.6% 37,039

YEAR 5 (1992) 18.0% 26,048

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6.1.2 Groundwater Banking AVEK’s groundwater banking programs store surplus water available from the SWP through groundwater recharge and include recovery wells to pump stored water in times of need. AVEK’s groundwater banks include the Westside Water Bank (started operations in 2010), Eastside Water Bank (started operations in 2016), Upper Amargosa Creek Recharge Project (started operations in 2019), and most recently the High Desert Water Bank. The Westside Water Bank has an estimated total storage capacity of 150,000 acre-feet (AF) and an estimated annual recharge capacity of 50,000 AFY. The Westside Water Bank includes 400 acres of groundwater recharge basins and 11 groundwater recovery wells. Up to 20 new wells may be constructed as a part of the Westside Water Bank project. Five irrigation wells existing on the property at the time of development may also be used in the program. AVEK meters the deliveries and recovery for the program and will not recover more than 90% of the amount recharged to account for evapotranspiration and other losses during recharge and conveyance as well as typical metering accuracy. The Eastside Water Bank has an estimated total storage capacity of 6,700 AF and an estimated annual recharge capacity of 2,000 AFY. The Eastside Water Bank consists of 80 acres, with three two-acre recharge basins and three groundwater wells. The project allows for recharge of untreated water that is later recovered and blended with treated water from the Eastside Water Treatment Plant. AVEK and partners—including Los Angeles County Waterworks Districts (LACWD), Palmdale Water District, and City of Palmdale—completed construction of the Upper Amargosa Creek Recharge Project in 2019. The project can recharge 1,600–2,350 AFY while preserving habitats for native animal species, including desert night lizards and coyotes, and providing additional flood protection. The project includes eight spreading basins, with a maximum capacity of 100 cubic feet per second during storms. The project was funded partly by Proposition 1E grant funds from DWR. AVEK is currently developing the High Desert Water Bank in the western portion of the Antelope Valley Groundwater Basin along the East Branch of the California Aqueduct. The new groundwater storage facility is a partnership between AVEK and the Metropolitan Water District of Southern California to increase water supply reliability south of the Delta. As the project expands and additional phases are constructed, AVEK will have dedicated capacity and the ability to recover stored imported water from the groundwater basin and pump the recovered water into the East Branch of the California Aqueduct for downstream deliveries to AVEK’s existing Water Treatment Facilities. The planned total storage capacity of the High Desert Water Bank will be 280,000 AF, with an estimated annual recharge capacity of 70,000 AFY. All AVEK water banks have a storage loss factor of 10%. Local recovery of SWP water from the groundwater banks has become an important source of water for AVEK to supplement annual SWP water allocations. AVEK began pumping water from the groundwater banks in 2014, once SWP had been recharged and groundwater production wells were in place. A summary of AVEK’s historical SWP deliveries to their banking sites is provided in Figure 6-4.

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Figure 6-4. 2011–2020 AVEK Historical SWP Deliveries to Groundwater Banking Sites 70,000

60,240 60,000 Total

50,000 Upper Armagosa Creek Recharge Project 40,000 Eastside Water Bank AFY 30,000 27,823 23,384

20,000 16,329 Westside Water Bank 12,831 14,086

10,000 7,213 High Desert Water Bank 371 0 0 0 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020

AVEK’s goal is to add storage in the groundwater banks so that the Agency is prepared to meet demands during three consecutive years of 10% Table A allocations from the SWP. AVEK currently has roughly 90,000 AF of SWP water stored within their banks for future recovery and is implementing infrastructure projects to expand its capacity to recharge water, recover water, and distribute recovered water. Based on the demand projections presented in Section 4.2, the target groundwater bank storage capacity and annual production capacity are projected in Figure 6-5.

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Figure 6-5. Projected AVEK Groundwater Banking Target Sizing

140,000 132,990 126,600 117,450 120,000 115,530

97,260 100,000

Target Storage Capacity (AF) 80,000 AFY 77,730 Target Production Capacity (AFY) or

AF 60,000 42,200 44,330 38,510 39,150 40,000 32,420

20,000 25,910

0 2020 2025 2030 2035 2040 2045

6.1.3 Water Quality DWR has conducted water quality monitoring for the SWP since 1968. Initially, this program sought to monitor eutrophication (an increase in chemical nutrients) and salinity in the SWP. Over time, the water quality program expanded to include parameters of concern for drinking water, recreation, and wildlife. Water quality samples are collected at regular intervals throughout the year for chemical, physical, and biological parameters. The coverage of this program includes more than 40 locations associated with the SWP, from the Feather River drainage in the north to Lake Perris in the south (California Department of Water Resources, 2020). In addition, AVEK routinely monitors for contaminants in the drinking water according to Federal and State laws. AVEK prepares an annual water quality report,1 which provides results of the monitoring efforts. Through monitoring and testing, AVEK has found that some contaminants exist; however, all State and Federal drinking water requirements have been met. The presence of contaminants does not necessarily pose a health risk, and all drinking water, including bottled water, may be reasonably expected to contain at least small amounts of some contaminants (Antelope Valley-East Kern Water Agency, 2020). The SWP water has moderate total organic carbon levels, resulting in higher disinfection byproduct (DBP) formation, and also has some taste- and odor causing compounds. AVEK’s conventional surface water treatment plants use a treatment process of flocculation, sedimentation basins, ozone, followed by biologically active filters, and chlorination. The ozone effectively removes the taste and odor compounds, but DBP formation is a concern due to only moderate organics removal through the treatment process, followed by chlorination. AVEK uses the Eastside Water Bank to blend with water

1 https://www.avek.org/water-quality-c1200b6 Antelope Valley-East Kern Water Agency 2020 Urban Water Management Plan May 2021 6-8 DRAFT

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from the Eastside Water Treatment Plant (WTP) to control DBPs, and uses the Westside Water Bank to serve the Rosamond WTP system to minimize DBPs due to the long detention time of water in the system. Other than controlling DBP formation, there are no water quality parameters identified to be of special concern to AVEK at this time (Carollo, 2020). Water Exchanges and Transfers AVEK takes part in water exchanges and water transfers with other State Water Contractors, including suppliers within the greater Antelope Valley, to help meet demands within the region. A water exchange is water delivered by one water user to another, with the receiving water user providing water in return at a specified time or when conditions of the parties’ agreement are met. A water transfer is a temporary or long-term change in the point in diversion, place of use, or purpose of use due to a transfer, sale, lease, or exchange of water or water rights. In the past 10 years, AVEK has executed 13 exchange agreements and eight transfer agreements totaling over 170,000 AF of water. In 2020, AVEK transferred or exchanged 11,286 AF of water to four agencies, as summarized in Table 6-4. Figure 6-6 summarizes exchanges and transfer volumes from 2011 to 2020.

Table 6-4. 2020 AVEK Exchanges and Transfers

DWR AGREEMENT NO. AMOUNT FROM AVEK TO ENTITY NAME DESCRIPTION (SWPAO#) OTHER AGENCIES (AF) Kern County WA/V Lions Table A Transfer 20-026 7,000

Littlerock Creek ID 1:1 Table A Exchange 07-031 1,380

Palmdale WD 1:1 Table A Exchange 18-032 1,500

Santa Clarita Valley WA 2:1 Table A Exchange 19-032 1,406

TOTAL 11,286

Source: AVEK

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Figure 6-6. 2011–2020 AVEK Annual Exchanges and Transfers Volumes

45,000

40,000 38,511 34,683 35,000 33,454

30,000

25,000 20,889 AF 20,000 19,012 14,812 15,000 11,286 10,000

5,000 0 0 132 0 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020

AVEK is developing a long-term exchange/storage program to further maximize the use of its SWP supplies and provide funding for purchase of additional water supplies. Other exchange programs are anticipated to be developed in the future to further secure the Agency’s water supplies. Potential exchange deliveries have not been included in AVEK’s projections of future water supplies. AVEK also has an agreement with LACWD District 40 (LACWD No. 40) to transfer groundwater supplies, which is discussed in Section 6.3.

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Groundwater AVEK’s groundwater wells are located within the Antelope Valley Groundwater Basin (“the Basin”). The Basin is a large, topographically closed alluvial basin with an estimated total storage capacity of about 68 to 70 million acre-feet. It consists of two primary aquifers: the upper unconfined aquifer (“principal aquifer”), which is the main source of groundwater for the area, and a lower aquifer that is considered to be confined. The Basin encompasses 1,580 square miles in Los Angeles, Kern, and San Bernardino counties. The groundwater basin boundaries have been defined by the California Department of Water Resources (DWR Basin Number 6-44). Prior to 1972, groundwater provided more than 90% of the total water supply in the Antelope Valley. Since 1972, it is estimated that between 50% to 90% of the area’s water supplies are from groundwater. Groundwater pumping peaked in the 1950s, and then declined as greater pumping lifts and increasing energy costs made the use of groundwater in the area less economical for agricultural uses. Groundwater levels in some areas have declined significantly since the early 1900s due to over- extraction According to the US Geological Service (USGS) (United State Geological Service (USGS), 2003), groundwater levels declined more than 200 feet in some parts of the Basin, resulting in increased pumping lifts, reduced well efficiency, and land subsidence of more than six feet in some areas. The Basin was adjudicated in 2015 after 15 years of complex proceedings among more than 4,000 parties, including public water suppliers, landowners, small pumpers and non-pumping property owners, and the Federal and State governments. The Antelope Valley Area of Adjudication covers approximately 1,390 square miles, or 90% of the groundwater basin. The Antelope Valley Groundwater Basin Adjudication Judgment (“Judgment”), included in Appendix F, determined the Basin is in a state of overdraft, established respective water rights among groundwater producers based on the Basin’s Native Safe Yield, and ordered a ramp-down of production to meet the Native Safe Yield by 2023. The adjudication defined a Native Safe Yield of 82,300 AFY. To achieve sustainable groundwater elevations, groundwater production will be reduced (ramped down) over a seven-year period (2016–2022) to a final Production Right. Following the adjudication, the Antelope Valley Watermaster was formed to implement the Judgment. The Watermaster is charged with administering the adjudicated water rights and managing the groundwater resources within the adjudicated portion of the Antelope Valley. Figure 1-1 shows the adjudication boundary in relation to AVEK’s service area. As shown in Table 6-5, the ramp-down period from 2016 to 2022 is causing substantial reductions in pumping in the Basin.

Table 6-5. Ramp-down Production Rights Within and Outside of AVEK’s Service Area, AFY

PRE-RAMP DOWN PRODUCTION RIGHTS POST-RAMP DOWN PRODUCTION RIGHTS AVEK 4,000.0 3,550.0

AVEK Customers 18,012.9 12,083.8

SUBTOTAL WITHIN AVEK SERVICE AREA 22,012.9 15,633.8

Non-AVEK Customers 114,007.3 66,666.2

TOTAL 136,020.2 82,300.0

Source: Judgement

There are seven potential production categories identified in the Judgment: production rights, ramp- down production, imported water return flows, carryover water, stored water, other rights to produce

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groundwater, and additional production. Production rights are divided into five categories: overlying production rights, non-overlying production rights, Federal Reserve water rights, small pumper class, and California production rights. Detailed information regarding each production category is available in the annual reports. The most recent available report is included in Appendix G. Of most relevance to AVEK are Overlying Production Rights and Non-Overlying Production Rights within the AVEK service area, because this groundwater is the primary supply other than imported water from AVEK. AVEK has an overlying production right of 3,550 AFY.

Table 6-6. Non-Overlying Producers’ Production Rights by AVEK Customers

PRODUCER PRODUCTION RIGHT (AFY) Boron Community Services District 50.0

California Water Services Company 343.1

Desert Lake Community Services District 73.5

LACWD No. 40 6,789.3

North Edwards Water District 49.0

Palm Ranch Irrigation District 465.7

Quartz Hill Water District 563.7

Rosamond Community Services District 404.4

West Valley County Water District 40.0

TOTAL 8,778.8

Note: From Judgment Table A-1 Exhibit 3. Excludes Palmdale Water District and Littlerock Creek Irrigation District. Both have their own SWP contracts.

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Table 6-7. Overlying Producers’ Production Rights by AVEK Customers

PRODUCER PRODUCTION RIGHT (AFY) 60th Street Association Water System 2.2

Antelope Park Mutual Water Company 169.9

Antelope Valley Mobile Estates 8.8

Aqua-J Mutual Water Company 44.4

Averydale Mutual Water Company 254.4

Baxter Mutual Water Company 35.0

Bleich Flat Mutual Water Company 33.5

Evergreen Mutual Water Company 68.5

Land Projects Mutual Water Company 613.5

Landale Mutual Water Company 155.6

Llano del Rio Water Company 279.0

Llano Mutual Water Company 0.0 Miracle Improvement Corporation dba 27.0 Golden Sands Mobile Home Park/Trailer Park Shadow Acres Mutual Water Company 51.7

Sundale Mutual Water Company 472.2

Tierra Bonita Mutual Water Company 40.3

West Side Park Mutual Water Co. 276.9

White Fence Farms Mutual Water Co. 772.1

NON-AVEK SUBTOTAL 3,305.0

AVEK 3,550.0

TOTAL WITHIN AVEK SERVICE AREA 6,855.0 Note: From Table A-2 Exhibit 4

In addition, parties listed on Exhibit 8 of the Judgment have a right to imported water return flows equal to the applicable percentage multiplied by the average amount of imported water used by that party within the Basin in the preceding five-year period. AVEK has rights to the return flows used by parties not on Exhibit 8 of the Judgment. For example, AVEK received 822 AF of groundwater in 2019 from imported water return flows. Return flows from agricultural imported water use are set in the Judgment at 34%, and return flows from municipal and industrial imported water use are set in the Judgment at 39% of the amount of imported water used.

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6.3.1 Groundwater Accounting As shown in Table 6-8, AVEK has not pumped any of its production rights the last five years. The only groundwater account that AVEK has used during the last five years is recovery of stored imported water. As a result, AVEK has increased available groundwater for future years through storage of carryover water and return flows. Also, AVEK has an agreement with LACWD to transfer groundwater on a non-permanent basis from AVEK to LACWD, which helps LACWD mitigate for its wells with poor water quality.

Table 6-8. Groundwater Volume Pumped (DWR 6-1W)

LOCATION, TYPE 2016 2017 2018 2019 2020 Antelope Valley Basin, Production Rights - - - - -

Antelope Valley Basin, Banked SWP Water 11,512 7,868 9,162 9,234 12,228

TOTAL: 11,512 7,868 9,162 9,234 12,228

6.3.2 Water Quality Groundwater quality in the upper aquifer is generally suitable for domestic, agricultural, and industrial use. Total Dissolved Solids (TDS) concentrations are in the range of 200 to 800 milligrams per liter (mg/L). The deep aquifer typically has higher TDS concentrations. Hardness levels range from 50 to 200 mg/L. High fluoride, boron, nitrates, hexavalent chromium, and arsenic are found in some areas of the Basin. However, AVEK has not had and does not anticipate groundwater quality issues with its wells.

Wastewater and Recycled Water AVEK does not provide supplemental treatment to recycled water and does not distribute recycled water. The Agency has no plans to provide recycled water as a part of its future deliveries. As a result, DWR Table 6-3, Table 6-4, and Table 6-5 have not been completed and are not included in the UWMP. Agencies within AVEK’s service area do collect, treat, and distribute recycled water. In accordance with the 2020 UWMP Guidebook, information regarding wastewater facilities and recycled water use within AVEK’s service area is provided below.

6.4.1 Recycled Water Coordination The most recent coordination to document the collection, treatment, and distribution of recycled water in the greater Antelope Valley region occurred as part of the Antelope Valley Integrated Regional Water Management Plan (IRWMP) 2019 update. Agencies responsible for operating, managing, and using the recycled water systems in the region are:  Los Angeles County Sanitation Districts (LACSD) Nos. 14 & 20  Los Angeles County Waterworks District No. 40  Palmdale Recycled Water Authority (includes the City of Palmdale and the Palmdale Water District)  Rosamond Community Services District (CSD)  Edwards Air Force Base (EAFB)

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6.4.2 Wastewater Collection, Treatment, and Disposal The greater Antelope Valley region’s municipal wastewater is generated from a combination of residential and commercial sources. The Cities of Lancaster and Palmdale own, operate, and maintain the wastewater collection systems in their respective service areas. In addition, the LACSD No. 14 and No. 20 serve the Antelope Valley. LACSD No. 14 serves a large portion of Lancaster, portions of Palmdale, and adjacent unincorporated areas of Los Angeles County. LACSD No. 20 provides wastewater management services for the Palmdale area as well as adjacent unincorporated Los Angeles County areas. Recycled water in the greater Antelope Valley is available from two primary sources, the Lancaster Water Reclamation Plant (WRP) and the Palmdale WRP. The LACSD owns and operates the Lancaster WRP and Palmdale WRP, which collect wastewater from the Cities of Palmdale and Lancaster. Wastewater is treated to tertiary levels that are suitable for non-potable uses and groundwater recharge. The Lancaster WRP has a permitted capacity of 18.0 million gallons per day (MGD) and in 2019 treated 15,052 AF, which is used for irrigation, agriculture, urban reuse, wildlife habitat, maintenance, and recreational impoundments. The Palmdale WRP has a permitted capacity of 12.0 MGD and in 2019 treated 9,021 AF of wastewater for agricultural and urban reuse. The Lancaster WRP collects most of the wastewater produced within the AVEK service area. The Rosamond CSD owns and operates the Rosamond Wastewater Treatment Plant (WWTP) located in the town of Rosamond. The Rosamond WWTP has a permitted capacity of 1.27 MGD and in 2019 treated 1,222 AF. The Rosamond WWTP currently produces secondary-treated water. In 2008, Rosamond CSD developed a plan to build a tertiary treatment plant with a potential for future expansion. However, construction to complete the upgrades is on hold indefinitely due to lack of funding and other economic considerations. EAFB has two treatment plants that distribute recycled water to the base. The EAFB Air Force Research Laboratory Treatment Plant is a secondary wastewater treatment plant that discharges all of its effluent to evaporation ponds at the base. In 2019, approximately 34 AF was sent to the evaporation ponds. The EAFB Main Base WWTP produces tertiary treated effluent for landscape irrigation at the base golf course, and excess effluent is discharged to the evaporation ponds, which totaled approximately 387 AF in 2019. The majority of the wastewater currently collected from within the LACWD No. 40 service area is treated and discharged outside its service area. However, recycled water from the Palmdale and Lancaster WRPs is projected to be a potential source of supply for LACWD No. 40 with completion of the Antelope Valley Backbone project. This project will provide the necessary distribution infrastructure to convey recycled water from the two WRPs to additional users in the Antelope Valley. To date, only a portion of the Antelope Valley Backbone has been constructed. AVEK’s retailers have projected increased use of recycled water to offset potable use, but to-date little progress has been made implementing recycled water projects within AVEK’s service area. Table 6-9 summarizes recycled water use projections from LACWD No. 40. For supply and demand analysis in this UWMP, no additional recycled water is assumed to be developed through 2045.

Table 6-9. Retail Recycled Water Projection Within AVEK Service Area

RETAILER 2020 2025 2030 2035 2040 LACWD No. 40 0 13,500 15,200 17,000 18,700

Source: LACWD No. 40 Draft 2020 UWMP (Brown & Caldwell, 2021).

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Surface Water AVEK does not have sources of surface water supply other than imported SWP water.

Stormwater AVEK does not intentionally divert stormwater for beneficial use.

Desalinated Water Opportunities AVEK has no plans for the development of desalinated water supplies within the planning horizon of this UWMP.

Future Water Projects A description of future projects that AVEK may implement to increase water supplies is provided below.

Westside Water Bank Improvements to the California Aqueduct for delivery to the AVEK’s banking partners. As the program Construction of permanent underground piping. expands, the Agency will also have recharge The project includes the replacement of and recovery capacity in the Bank to meet temporary irrigation piping with permanent increase local demands and improve water buried pipelines and appurtenances, which will supply resiliency. improve the ability to achieve the recharge goals at the bank during wet years. South-North Intertie Pipeline Phase 2 The South-North Intertie Pipeline Phase II Eastside Water Bank Expansion Project (SNIP Ph II) includes the construction of The expansion project will significantly increase a 6.5 mile 48-inch diameter potable water the recharge capacity of the bank by building 85 pipeline and equipping the existing pump acres of recharge basins, providing 10,400 AFY station with new pumps. The new pipeline will of additional capacity (for a total capacity of tie into AVEK’s existing South North Intertie 11,600 AFY). The project also includes well Pipeline and connect the Westside Water Bank equipping to provide an additional 300 gpm of to the Quartz Hill Water Treatment Plant. recovery capacity. Environmental review, feasibility study, and property acquisition are complete. Final design Enterprise / High Desert Water Bank is nearly complete (90%). Construction of the Expansion pipeline will allow access to up to 75,000 AF of water currently stored in the Westside Water Development of a new groundwater recharge Bank and enable delivery throughout the AVEK and recovery facility, including recharge basins service area. and pipelines, groundwater recovery wells, well collection system, and transmission and pumping facilities to deliver water from the bank

6.8.1 New Supplemental Water Supply (per LACWD MOU) LACWD is required to acquire new supplemental water supplies for any new growth. Per the memorandum of understanding (MOU) agreement with LACWD, AVEK will acquire the supplies on behalf of LACWD, and AVEK will deliver the water to LACWD along with AVEK’s existing supplies. The supplies can be: (a) water supply originating outside the Basin and imported into the Basin by

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AVEK in addition to AVEK’s SWP Table A annual allocation; (b) water supply generated by AVEK groundwater production rights; and (c) any other water supply generated through AVEK’s acquisition of any other water right. Since LACWD represents roughly 70% of AVEK retailer sales, new supply volumes equivalent to 70% of new demand are assumed to be added to supplies over time, as shown in Table 6-10. The new supplemental water supplies are assumed to have greater reliability than SWP Table A supplies based on the mix of supplies.

Table 6-10. Projected New Supplemental Water Supplies (per LACWD MOU)

2025 2030 2035 2040 2045 Total AVEK Service Area Demand 6,990 13,970 17,420 21,090 24,770

New Supply (per LACWD MOU) (70% of Total) 4,890 9,780 12,190 14,760 17,340

Summary of Projected Water Supplies AVEK’s primary water supplies consist of the following sources:

SWP, Table A Allocation Average yield based on DWR 2019 DCR and presented in Table ES-3.

Antelope Valley Groundwater Basin Production Rights Based on the Judgment.

Antelope Valley Groundwater Basin Imported Water Return Flows Estimate based on projected imported water demands for parties not on Exhibit 8 of the Judgment.

New Supplemental Water Supplies (per LACWD MOU) Estimated based on projected new demand from LACWD, presented in Section 6.8.1.

The projected reasonably available volumes summarized in Table 6-11. In addition, AVEK can supplement supplies by recovering banked SWP water in groundwater or accessing supplies, if available, such as carryover groundwater or SWP water types other than Table A.

Table 6-11. Projected Water Supplies (DWR Table 6-9W)

2025 2030 2035 2040 2045 SWP Table A 81,840 79,660 77,490 75,320 75,320

Groundwater, Production Rights 3,550 3,550 3,550 3,550 3,550

Groundwater, Imported Water Return Flows 800 800 800 800 800

New Supply (per LACWD MOU) 4,890 9,780 12,190 14,760 17,340

TOTAL 91,080 93,790 94,030 94,430 97,010

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6.9.1 Climate Change Effects Climate models disagree on average annual precipitation projections but agree on other hydrologic metrics relevant to water resources management, including (Persad, 2020) (Partida, 2020):  Snowpack declines  Increased fraction of precipitation on extreme rainfall days  Shorter, sharper rainy season  Increased evapotranspiration  Higher frequency of extremely wet and extremely dry years  Higher incidence of extremely dry year followed an extremely wet year, or vice versa

As discussed at greater length in the 2019 Antelope Valley IRWMP (Antelope Valley Integrated Regional Water Management Group, 2019), climate change is expected to increase average temperature by at least 5 degrees Fahrenheit by 2100. Despite the potential minimal impact on total annual precipitation, climate change is expected to result in a larger proportion of precipitation coming in the form of intense single-day events. The largest impact of climate change on AVEK will likely be seen from SWP availability. The DWR 2019 DCR included a model study representing hydrologic and sea level rise conditions at 2040 to evaluate SWP supply availability under future conditions. The future condition study used the same model assumptions as the study under existing conditions but reflected changes expected to occur from climate change, specifically projected temperature and precipitation changes centered around 2035 (2020 to 2049) and a 45 centimeter sea level rise. The long-term average allocations reported for the future conditions study from 2019 DCR is applied starting in 2040, with a straight-line decrease from existing conditions, as described in Section 6.1.1 and presented in in Table ES-3. Energy Intensity AVEK must include information that could be used to calculate the energy intensity of their water service per Water Code Section 10631.2.(a). AVEK water service energy intensity was estimated based on readily available electrical billing data and water production data. AVEK compiled electrical billing records from 2017 through 2020 and calculated the annual electrical consumption for its treatment plants and distribution system combined. The analysis focused on treated water deliveries because untreated water deliveries are typically via gravity from the California Aqueduct, and AVEK transfers and exchanges are outside of its service area. Based on this information, AVEK’s average water service energy intensity was 261 kilowatt hours per AF (kWh/AF) of treated water delivered, as shown in Table 6-12.

Table 6-12. 2017–2020 AVEK Energy Intensity Estimates

2017 2018 2019 2020 2017-2020 TOTAL Electricity (kWh) 8,616,000 9,909,000 10,941,000 11,031,000 40,497,000

Treated Water Deliveries (AF) 34,205 39,058 40,858 40,960 155,082

ENERGY INTENSITY (KWH/AF) 252 254 268 269 261

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URBAN WATER MANAGEMENT PLAN Water Supply Reliability and Drought Risk Assessment This chapter evaluates AVEK’s water supply reliability under various drought and non-drought conditions and shows the benefits of AVEK’s investment in groundwater banking to manage the high variability of SWP water.

This chapter describes the reliability of the Antelope Valley-East IN THIS SECTION

Kern Water Agency (AVEK or Agency) water supply. It presents  Water Supply 25-year projections for normal, single dry, and multiple dry Reliability Assessment years, and assesses the drought risk over the next five years. Water supply reliability reflects AVEK’s ability to meet the water  Drought Risk Assessment needs of its customers with water supplies under varying conditions. The analysis considers plausible hydrological and regulatory variability, climate conditions, and other factors that affect the Agency’s water supply and demand. AVEK’s water sources and their constraints are described in detail in Chapter 6. The primary constraint on availability of State Water Project (SWP) supplies has been extreme drought conditions, and SWP availability depends on rainfall, snowpack, runoff, reservoir storage, pumping capacity of SWP facilities, and regulatory and environmental mandates on SWP operations. The 2019 SWP Delivery Capability Report (DCR) (California Department of Water Resources, 2020) provides SWP water supply availability under both existing (2020) and future (2040) conditions. AVEK has invested in its groundwater banking programs to stabilize the swings in SWP water availability by storing surplus SWP water through groundwater recharge and pumping from recovery wells in times of need. The following sections analyze the performance of AVEK’s supplies under different conditions.

7-1

Water Supply Reliability and Drought Risk Assessment Section 7

Water Supply Reliability Assessment This section presents AVEK’s expected water supply reliability for a normal year, single dry year, and five consecutive dry years, including projections for 2025, 2030, 2035, 2040, and 2045.

AVEK’s supplies for this assessment include:

SWP Table A Allocation Yield based on the California Department of Water Resources (DWR) 2019 DCR, described in Section 6.1.1 and summarized below.

Antelope Valley Groundwater Basin Production Rights 3,550 acre-feet per year (AFY) based on the Stipulated Judgment (Judgment) for the 2015 Antelope Valley Groundwater Adjudication.

Antelope Valley Groundwater Basin Imported Water Return Flows 800 AFY based on projected imported water demands for parties not on Exhibit 8 of the Judgment.

New Supplemental Water Supply (per MOU with Los Angeles County Waterworks Districts (LACWD)) Average supply yield based on projected new demand from LACWD, presented in Section 6.8.1. The new supplemental water supplies are assumed to have greater reliability than SWP Table A supplies based on the mix of supplies.

Antelope Valley-East Kern Water Agency 7-2 2020 Urban Water Management Plan

Water Supply Reliability and Drought Risk Assessment Section 7

7.1.1 Water Supply Reliability – Normal Year Average SWP Table A allocation is projected to decrease from 58% in 2020 to 52% in 2040 as shown in Table 7-1. Total normal year AVEK supplies are shown in

Figure 7-1 and, based on these assumptions, AVEK has sufficient supplies in normal years and could use available supplies to add groundwater storage for dry periods. For example, SWP water could be recharged when available, or unused groundwater rights can be carried over for use in future years.

Table 7-1. SWP Average Yield Projections

2020 2025 2030 2035 2040 2045 Average Table A Allocation (%) 58.0% 56.5% 55.0% 53.5% 52.0% 52.0%

Average Table A Yield (AFY) 84,010 81,840 79,660 77,490 75,320 75,320

Figure 7-1. AVEK Supply and Demand Projections, Normal Year

120,000

97,010 Total AVEK Supplies 100,000 93,790 94,030 94,430 91,080

4,890 9,780 12,190 14,760 17,340 4,350 4,350 80,000 4,350 4,350 4,350

60,000 AFY 57,590 55,210 Total AVEK Demand 50,990 51,880 44,440 40,000

New Supply (per LACWD MOU) 20,000 AVEK Groundwater

AVEK SWP Table A 81,840 79,660 77,490 75,320 75,320 0 2025 2030 2035 2040 2045

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Water Supply Reliability and Drought Risk Assessment Section 7

7.1.2 Water Supply Reliability – Single Dry Year Single dry year yield for SWP water is based on actual 2014 and 2021 (as of May 2021) allocation of 5%. Groundwater rights are not impacted by short-term drought conditions, so normal year groundwater yield assumptions are applied. The new supplemental water supplies (per LACWD MOU) are assumed to have greater reliability than SWP Table A supplies based on the mix of supplies. The remainder of demand is met with groundwater in storage. As discussed in Section 6.1.2, AVEK’s annual banking recovery target is to produce at least enough groundwater to meet demand with 10% Table A allocations from the SWP. As shown in Figure 7-2, groundwater bank supplies enable AVEK to meet its demands in a single dry year.

Figure 7-2. AVEK Supply and Demand Projections, Single Dry Year

70,000

60,000 57,590 Total AVEK Demand 55,210 50,990 51,880 50,000 44,440 28,660 40,000 28,860 28,100 29,620 AFY 30,000 27,960

AVEK Groundwater Bank 17,340 20,000 14,760 12,190 9,780 New Supply 4,890 (per LACWD MOU) AVEK Groundwater 10,000 4,350 4,350 4,350 4,350 4,350 AVEK SWP Table A 7,240 7,240 7,240 7,240 7,240 0 2025 2030 2035 2040 2045

Antelope Valley-East Kern Water Agency 7-4 2020 Urban Water Management Plan

Water Supply Reliability and Drought Risk Assessment Section 7

7.1.3 Water Supply Reliability – Five Consecutive Dry Years For multiple dry years, SWP water availability is based on 1988 to 1992 simulated yield from the 2019 SWP DCR, which estimated the following annual Table A allocation:  Year 1 (1988) 12.3%  Year 2 (1989) 32.2%  Year 3 (1990) 13.3%  Year 4 (1991) 25.6%  Year 5 (1992) 18.0% Similar to single dry year, new supplemental water supplies (per LACWD MOU) are assumed to have greater reliability than SWP Table A supplies, groundwater rights are not impacted by an extended drought, and groundwater bank supplies are used to meet remaining demands. Table 7-2 summarizes AVEK supply and demand totals for the multiple dry year scenario.

Table 7-2. Multiple Dry Years Supply and Demand Comparison (DWR Table 7-4W)

- - 2025 2030 2035 2040 2045

First Supply Totals 44,440 50,990 51,880 55,210 57,590 Year Demand Totals 44,440 50,990 51,880 55,210 57,590

‐ DIFFERENCE: 0 0 0 0 0 55,920 60,810 63,220 65,790 68,370 Second Supply Totals Year Demand Totals 44,440 50,990 51,880 55,210 57,590

‐ DIFFERENCE: 11,480 9,820 11,340 10,580 10,780

Third Supply Totals 44,440 50,990 51,880 55,210 57,590 Year Demand Totals 44,440 50,990 51,880 55,210 57,590

‐ DIFFERENCE: 0 0 0 0 0 46,280 51,170 53,580 56,150 58,730 Fourth Supply Totals Year Demand Totals 44,440 50,990 51,880 55,210 57,590

‐ DIFFERENCE: 1,840 180 1,700 940 1,140

Fifth Supply Totals 44,440 50,990 51,880 55,210 57,590 Year Demand Totals 44,440 50,990 51,880 55,210 57,590

‐ DIFFERENCE: 0 0 0 0 0

Note: Supply equals demand because AVEK would extract groundwater stored in local groundwater banks to meet supply shortfalls.

Antelope Valley-East Kern Water Agency 7-5 2020 Urban Water Management Plan

Water Supply Reliability and Drought Risk Assessment Section 7

As discussed in Section 6.1.2, AVEK’s total banking storage target is at least enough groundwater to meet demand with 10% Table A allocations from the SWP for three consecutive years. Figure 7-3 presents the total volume used from AVEK’s groundwater bank during a multiple year drought compared with the target total storage volume. As shown in the figure, additional groundwater bank supplies would be available if the five-year drought continued.

Figure 7-3. AVEK Groundwater Bank Storage Capacity vs. Use During Five Consecutive Dry Years

160,000

140,000 137,650 131,190 120,000 119,850 122,220 Total Use of Groundwater Bank 100,000 102,680

Target Storage Capacity

AF 80,000

60,000

40,000

45,880 20,000 39,950 40,740 43,730 34,230

0 2025‐2029 2030‐2034 2035‐2039 2040‐2044 2045‐2049

Antelope Valley-East Kern Water Agency 7-6 2020 Urban Water Management Plan

Water Supply Reliability and Drought Risk Assessment Section 7

2021–2025 Drought Risk Assessment Water Code Section 10635(b) is a new provision of the Water Code that requires a Drought Risk Assessment (DRA) for the upcoming five years (2021 to 2025) based on the five driest years on record.

The supply assumptions are similar to the multiple dry year assumptions in the previous section:

SWP Table A Allocation Yield based on five years with lowest yield from the DWR 2019 DCR, 1988 to 1992.

Antelope Valley Groundwater Basin Production Rights Reducing ramp-down production rights from 3,730 AFY in 2021 to 3,550 AFY production rights in 2023.

Antelope Valley Groundwater Basin Imported Water Return Flows 800 AFY based on projected imported water demands for parties not on Exhibit 8 of the Judgment. (This value is a rough estimate because it can change over time).

New Supplemental Water Supplies (per LACWD MOU) Straight-line supply increase from 2020 (none) to 2025 (4,890 AFY).

AVEK Groundwater Bank Used to meet remaining demand and sized to meet demands in a year with SWP Table A 5% allocation.

AVEK currently has roughly 90,000 AF of SWP water stored within its banks for future recovery and is implementing infrastructure projects to expand its capacity to recharge water, recover water, and distribute recovered water. As shown in Table 7-3, AVEK still would have over 40,000 AF of groundwater remaining in storage at the end of a five-year drought that starts in 2021.

Table 7-3. AVEK Supply Projections for 2021–2025 Drought Risk Assessment

SUPPLIES 2021 2022 2023 2024 2025

SWP, Table A 17,850 46,680 19,280 37,040 26,050

AVEK Groundwater 4,530 4,480 4,430 4,380 4,350

New Supply (per LACWD MOU) 980 1,960 2,940 3,920 4,890

SWP from Groundwater Bank 15,700 0 15,940 0 9,150

TOTAL AVEK SUPPLIES 39,060 53,120 42,590 45,340 44,440

Note: Groundwater bank supplies are used to meet remaining demand.

Antelope Valley-East Kern Water Agency 7-7 2020 Urban Water Management Plan Water Supply Reliability and Drought Risk Assessment Section 7

Figure 7-4. 2021–2025 AVEK Drought Reliability Assessment

140,000

120,000 Groundwater Bank Storage (at end of year) 100,000 SWP from Groundwater Bank 74,300

80,000 New Supply AF 74,300 58,360 (per LACWD MOU)

or 58,360 49,210

AFY 60,000 AVEK Groundwater

SWP, Table A 42,590 43,340 44,440 40,000 39,060 40,930

AVEK Demand 20,000

0 2021 2022 2023 2024 2025

Antelope Valley-East Kern Water Agency 7-8 2020 Urban Water Management Plan

URBAN WATER MANAGEMENT PLAN Water Shortage Contingency Plan This Water Shortage Contingency Plan describes how AVEK intends to respond to foreseeable and unforeseeable water shortages. This chapter provides an overview. The full plan is in Appendix H.

This Water Shortage Contingency Plan (WSCP) is a detailed plan for how the Antelope Valley-East Kern Water Agency (AVEK or Agency) intends to respond to foreseeable and unforeseeable water shortages. A water shortage occurs when the water supply is reduced to a level that cannot support typical demand at any given time. The WSCP provides guidance by identifying response actions to allow for efficient management of any water shortage with predictability and accountability. The tools in the WSCP enable AVEK to maintain reliable supplies and reduce the impact of supply interruptions due to extended drought or catastrophic supply interruptions.

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Water Shortage Contingency Plan Section 8

The WSCP describes the following:

1. Water supply reliability analysis: Summarizes AVEK’s water supply analysis and reliability, and identifies any key issues that may trigger a shortage condition.

2. Annual water supply and demand assessment procedures: Describes the key data inputs, evaluation criteria, and methodology for assessing the system’s reliability for the coming year and the steps to formally declare any water shortage levels and response actions.

3. Standard shortage stages: Establishes water shortage levels to clearly identify and prepare for shortages.

4. Shortage response actions: Describes the response actions that may be implemented or considered for each stage to reduce gaps between supply and demand, and to minimize social and economic impacts to the community.

5. Communication protocols: Describes communication protocols under each stage to ensure customers, the public, and government agencies are informed of shortage conditions and requirements.

6. Compliance and enforcement: This section is not applicable to wholesalers such as AVEK.

7. Legal authority: Lists the legal ordinance that grants AVEK the authority to declare a water shortage and implement and enforce response actions.

8. Financial consequences of WSCP implementation: Describes the anticipated financial impact of implementing water shortage stages and identifies mitigation strategies to offset financial burdens.

9. Monitoring and reporting: This section is not applicable to wholesalers such as AVEK.

10. WSCP refinement procedures: Describes the factors that may trigger updates to the WSCP and outlines how to complete an update.

11. Special water features distinctions: This section is not applicable to wholesalers such as AVEK.

12. Plan adoption, submittal, and availability: Describes the process for the WSCP adoption, submittal, and availability after each revision.

The 2021 WSCP is a stand-alone document that can be modified as needed. It is included as Appendix H.

Antelope Valley-East Kern Water Agency 8-2 2020 Urban Water Management Plan

URBAN WATER MANAGEMENT PLAN Demand Management Measures This chapter describes AVEK’s implementation of wholesale demand management measures intended to promote water use efficiency and partner with retail agencies to support sustainable management of regional water supplies.

Demand management is an integral part of sustainably IN THIS SECTION managing water resources in California. Implementation of  Metering demand management measures (DMMs) that help lower  Public Education and demand can improve water supply reliability and help meet both Outreach state and regional water conservation goals. This chapter  Conservation describes the Antelope Valley-East Kern Water Agency’s Staffing

(AVEK or Agency) efforts as a wholesale water supplier to  Asset Management promote conservation and reduce demands on water supplies. AVEK has been a leader in water use efficiency for many years. The Agency actively collaborates with local and regional agencies and the communities it serves to support innovative programs that drive change. AVEK implements DMMs as part of its ongoing operations, which are detailed in the following sections.

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Demand Management Measures Section 9

Demand Management Measures for Wholesale Suppliers AVEK’s system is fully metered, and unmetered connections have never been operated. AVEK charges all customers based on metered readings and established rate schedules. All current and new connections, including temporary connections, are required to be metered and billed per volume of use. Existing meters are regularly checked for leakage and accuracy.

Public Education and Outreach A summary of public education and outreach measures implemented by AVEK are as follows:  AVEK was the lead agency in the formation of the Antelope Valley Water Conservation Coalition (AVWCC). The AVWCC includes water districts, cities, builders, landscapers, designers, legislators, and other interested parties within the region. Water conservation in the greater Antelope Valley region is discussed during regular meetings, and the coalition provides periodic public education messaging regarding water conservation issues.  AVEK was the lead agency and principal funding source for the development of the website AVSavesWater.com, which provided information on water conservation, water smart landscaping, resources, and rebate opportunities. The content is now hosted at avswca.org.  AVEK sponsored water conservation grant programs in 2014 and 2015 to supporting customer conservation projects, focusing on turf buyback programs. A total of $430,000 was made available to the grant programs in fiscal years 2014 and 2015.  AVEK was the lead agency and principal funding source for the Antelope Valley State Water Contractors Association’s Water Conservation/SMART Landscaping Expos, which were held from 2014 to 2019. (The 2020 event was canceled due to COVID-19 safety restrictions.)

Water Conservation Program Coordination and Staffing AVEK has designated a Water Conservation Program Coordinator and has established a water conservation group as part of their Board of Directors’ Public Information Committee, which meets regularly. The program coordinator leads implementation of ongoing water conservation efforts described in this chapter and the Water Shortage Contingency Plan in Appendix H.

Antelope Valley-East Kern Water Agency 9-2 2020 Urban Water Management Plan

Demand Management Measures Section 9

Asset Management AVEK maintains its facilities according to the operations and maintenance manuals for its various facilities and equipment. In addition, AVEK conducts periodic inspections to assess the conditions of facilities and recommend needed repairs or improvements. AVEK audits system losses monthly as a part of its normal billing procedures. Pipelines are driven regularly as part of water sample runs, during which personnel will note leaks if observed. The Agency repairs leaks promptly, on average about twice per year. The Agency’s average long-term system loss is about 2% to 3%, which is considered to be within the margin of error and normal.

AVEK understands the importance of maintaining its capital facilities and has included the development of a formal asset management plan under the Capital and Human Resources Stewardship Goal of its 2015 Five-Year Strategic Plan as shown below:  Goal 5: Capital and Human Resources Stewardship — AVEK will be efficient and thoughtful stewards of our human and capital resource assets.  Strategy 2: Maintain capital facilities to ensure optimum facility life:  Objective 1: Develop an Asset Management Plan  Objective 2: Maintain facilities operational support

AVEK is in the process of completing a Water System Management Plan (WSMP). The WSMP will evaluate the performance and condition of AVEK’s potable water system under existing conditions and future conditions. The WSMP is intended to be a strategic document that guides AVEK with prioritization and decision-making regarding future water system improvements through the planning horizon of 2040 and build-out conditions. The goal of the WSMP is to assist AVEK in the planning and development of potable water system facilities to allow the Agency to reliably and efficiently serve water to its current customers, meet future growth, and respond to emergencies. Chapter 7 of the WSMP specifically describes the capacity evaluations of the water system under existing and future delivery needs, water system hydraulics under existing and future delivery needs, and existing system replacement.

Wholesale Supplier Assistance Programs AVEK’s Wholesale Supplier Assistance Programs are described in Section 9.2.

Antelope Valley-East Kern Water Agency 2020 Urban Water Management Plan May 2021 9-3 DRAFT

URBAN WATER MANAGEMENT PLAN Plan Adoption, Submittal, and Implementation This chapter describes the steps taken to adopt, submit, and make publicly available the 2020 UWMP, 2021 WSCP, and Appendix J addendum to the 2015 UWMP.

The 2020 Urban Water Management Plan (UWMP), 2021 Water IN THIS SECTION

Shortage Contingency Plan (WSCP), and 2015 UWMP  UWMP Preparation addendum were prepared in a transparent manner, and the and Adoption Notification Antelope Valley-East Kern Water Agency (AVEK or Agency) actively engaged stakeholders, cities, counties, water agencies,  Public Hearing and Adoption and the public to both seek and distribute information about water  Plan Submittal to the use, supply, and reliability to strengthen the region’s ability to State assess and plan for its water future.

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Plan Adoption, Submittal, and Implementation Section 10

Inclusion of All 2020 Data Water Code Section 10621(b) requires that suppliers notify cities and counties in which they serve water that the UWMP and WSCP are being updated and reviewed at least 60 days prior to the public hearing.

To fulfill this requirement, AVEK sent letters of notification of preparation to the following cities and counties within AVEK’s service area 60 days prior to the public hearing: City of California City City of Palmdale Los Angeles County City of Lancaster Kern County Ventura County

In addition, AVEK notified their retail customers. Copies of the 60-day notification letters are attached as Appendix D. AVEK made the 2020 UWMP, 2021 WSCP, and 2015 UWMP addendum available for public review on May 25, 2021, and held a public hearing on June 8, 2021. The notice to the public was made once a week for two successive weeks. The public hearing was first noticed in the Valley Press on May 26, 2021, and noticed again on June 2, 2021. The hearing notices are attached as Appendix D. Prior to the public hearing, AVEK maintained a copy of the 2020 UWMP, 2021 WSCP, and 2015 UWMP addendum in its office and on the Agency’s website at www.avek.org.

Notice of Public Hearing The 2020 UWMP, 2021 WSCP, and 2015 UWMP addendum were included as separate agenda items, noticed, and reviewed in a public hearing at the regularly scheduled AVEK Board of Directors meeting on June 8, 2021. This hearing provided cities, counties, and members of the public a chance to review the report and provide comment. The public hearing took place before the adoption, allowing opportunity for the report to be modified in response to public input. The 2020 UWMP, 2021 WSCP, and 2015 UWMP addendum were adopted by AVEK’s Board of Directors on June 22, 2021. A copy of each Resolution of Adoption is included as Appendix E.

Submittal of the UWMP and WSCP The 2020 UWMP, 2021 WSCP, and 2015 UWMP addendum were submitted to the California Department of Water Resources (DWR) by July 1, 2021 using the DWR Water Use Efficiency Data Portal. The documents were also sent to the California State Library and to all cities and counties within AVEK’s service area within 30 days of adoption.

Public Availability Commencing no later than July 1, 2021, AVEK will have a copy of the 2020 UWMP, 2021 WSCP, and 2015 UWMP addendum available for public review at the AVEK office (see address below) during normal business hours. Antelope Valley-East Kern Water Agency 6500 W. Avenue N Palmdale, CA 93551 The documents also will be posted on the Agency’s website at www.avek.org.

Antelope Valley-East Kern Water Agency 10-2 2020 Urban Water Management Plan

URBAN WATER MANAGEMENT PLAN References

Antelope Valley Integrated Regional Water Management Group. (2019). Antelope Valley Integrated Regional Water Management Plan. Retrieved from https://pw.lacounty.gov/wwd/avirwmp/index.cfm California Department of Water Resources. (2018). Resource Guide for Climate Change Data and Guidance. Retrieved from https://water.ca.gov/-/media/DWR-Website/Web- Pages/Programs/Groundwater-Management/Sustainable-Groundwater- Management/Best-Management-Practices-and-Guidance-Documents/Files/Resource- Guide-Climate-Change-Guidance_v8_ay_19.pdf California Department of Water Resources. (2020). 2019 State Water Project Delivery Capability Report. California Department of Water Resources. (November 2018). Making Water Conservation a California Way of Life. Carollo. (2020). Water Master Plan - Antelope Valley-East Kern Water Agency. Department of Water Resources. (2021, March). Urban Water Management Plans. Retrieved from California Department of Water Resources: https://water.ca.gov/Programs/Water- Use-And-Efficiency/Urban-Water-Use-Efficiency/Urban-Water-Management-Plans Kern County Counil of Governments. (2018). General Land Use Plan . Partida, C. K. (2020, November 15). Planning for a shorter rainy season and more frequent extreme storms in California. California WaterBlog. Retrieved from https://californiawaterblog.com/2020/11/15/planning-for-a-shorter-rainy-season-and- more-frequent-extreme-storms-in-california/ Persad, G. G. (2020, October). Inter-model agreement on projected shifts in California hydroclimate characteristics critical to water management. Climatic Change. Retrieved from https://doi.org/10.1007/s10584-020-02882-4 Southern California Association of Governments. (2020). The 2020 - 2045 Regiona Transporation Plan / Sustainable Communities Strategy (Connect SoCal).

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A

Appendix A: 2020 UWMP DWR Checklist

Antelope Valley-East Kern Water Agency 2020 Urban Water Management Plan May 2021 A DRAFT

AVEK 2020 UWMP Appendix A - DWR UWMP Checklist

2020 2020 UWMP Guidebook Summary as Applies to UWMP Subject Location Location A plan shall describe and evaluate sources of supply, reasonable and practical efficient uses, Introduction and Executive Chapter 1 reclamation and demand management activities. Overview Summary Each plan shall include a simple description of the supplier’s plan including water availability, Executive Chapter 1 future requirements, a strategy for meeting needs, and other pertinent information. Additionally, a Summary Summary supplier may also choose to include a simple description at the beginning of each chapter. Every person that becomes an urban water supplier shall adopt an urban water management Section 2.2 Plan Preparation N/A plan within one year after it has become an urban water supplier. Coordinate the preparation of its plan with other appropriate agencies in the area, including other Section 2.6 water suppliers that share a common source, water management agencies, and relevant public Plan Preparation Section 2.3 agencies, to the extent practicable. Provide supporting documentation that the water supplier has encouraged active involvement of Section 2.6.2 diverse social, cultural, and economic elements of the population within the service area prior to Plan Preparation Appendix D and during the preparation of the plan and contingency plan. Wholesale suppliers will include documentation that they have provided their urban water DWR Table Section 2.6 suppliers with identification and quantification of the existing and planned sources of water System Supplies 2-4W available from the wholesale to the urban supplier during various water year types. Section 3.1 Describe the water supplier service area. System Description Section 3.1 Section 3.3 Describe the climate of the service area of the supplier. System Description Section 3.2 Section 3.4 Provide population projections for 2025, 2030, 2035, 2040 and optionally 2045. System Description Section 3.3 Describe other social, economic, and demographic factors affecting the supplier’s water Section 3.4.2 System Description Section 3.3 management planning. Sections 3.4 System Description and Indicate the current population of the service area. Section 3.3 and 5.4 Baselines and Targets Section 3.5 Describe the land uses within the service area. System Description Section 3.4 Section 4.2 Quantify past, current, and projected water use, identifying the uses among water use sectors. System Water Use Chapter 4 Section 4.2.4 Retail suppliers shall provide data to show the distribution loss standards were met. System Water Use Section 4.2.7 In projected water use, include estimates of water savings from adopted codes, plans and other Section 4.2.6 System Water Use Section 4.2 policies or laws. Section 4.2.6 Provide citations of codes, standards, ordinances, or plans used to make water use projections. System Water Use Section 4.2 Demands under climate change considerations must be included as part of the drought risk Section 4.5 System Water Use Section 4.2.4 assessment.

A-1 AVEK 2020 UWMP Appendix A - DWR UWMP Checklist

2020 2020 UWMP Guidebook Summary as Applies to UWMP Subject Location Location Wholesale suppliers shall include an assessment of present and proposed future measures, Section 5.1 Baselines and Targets Chapter 5 programs, and policies to help their retail water suppliers achieve targeted water use reductions. Sections 6.1 Provide a discussion of anticipated supply availability under a normal, single dry year, and a System Supplies Chapter 6 and 6.2 drought lasting five years, as well as more frequent and severe periods of drought. Provide a discussion of anticipated supply availability under a normal, single dry year, and a Sections 6.1 drought lasting five years, as well as more frequent and severe periods of drought, including System Supplies Section 6.9.1 changes in supply due to climate change. When multiple sources of water supply are identified, describe the management of each supply Chapter 6 Section 6.1 System Supplies in relationship to other identified supplies. introduction Section 6.1.1 Describe measures taken to acquire and develop planned sources of water. System Supplies Section 6.8 Identify and quantify the existing and planned sources of water available for 2020, 2025, 2030, Section 6.2.8 System Supplies Section 6.9 2035, 2040 and optionally 2045. Section 6.2 Indicate whether groundwater is an existing or planned source of water available to the supplier. System Supplies Section 6.3 Indicate whether a groundwater sustainability plan or groundwater management plan has been Section 6.2.2 adopted by the water supplier or if there is any other specific authorization for groundwater System Supplies Section 6.3 management. Include a copy of the plan or authorization. Section 6.2.2 Describe the groundwater basin. System Supplies Section 6.3 Indicate if the basin has been adjudicated and include a copy of the court order or decree and a Section 6.2.2 System Supplies Section 6.3 description of the amount of water the supplier has the legal right to pump. For unadjudicated basins, indicate whether or not the department has identified the basin as a Section 6.2.2.1 high or medium priority. Describe efforts by the supplier to coordinate with sustainability or System Supplies N/A groundwater agencies to achieve sustainable groundwater conditions. Provide a detailed description and analysis of the location, amount, and sufficiency of Section 6.2.2.4 System Supplies Section 6.3 groundwater pumped by the urban water supplier for the past five years Provide a detailed description and analysis of the amount and location of groundwater that is Section 6.2.2 System Supplies Section 6.3 projected to be pumped. Describe the opportunities for exchanges or transfers of water on a short-term or long- term Section 6.2.7 System Supplies Section 6.2 basis. Describe the quantity of treated wastewater that meets recycled water standards, is being System Supplies Section 6.2.5 N/A discharged, and is otherwise available for use in a recycled water project. (Recycled Water) System Supplies Section 6.2.5 Describe the recycled water currently being used in the supplier's service area. Section 6.4 (Recycled Water) Describe and quantify the potential uses of recycled water and provide a determination of the System Supplies Section 6.2.5 N/A technical and economic feasibility of those uses. (Recycled Water)

A-2 AVEK 2020 UWMP Appendix A - DWR UWMP Checklist

2020 2020 UWMP Guidebook Summary as Applies to UWMP Subject Location Location Describe the projected use of recycled water within the supplier's service area at the end of 5, System Supplies Section 6.2.5 10, 15, and 20 years, and a description of the actual use of recycled water in comparison to uses N/A (Recycled Water) previously projected. Describe the actions which may be taken to encourage the use of recycled water and the System Supplies Section 6.2.5 N/A projected results of these actions in terms of acre-feet of recycled water used per year. (Recycled Water) System Supplies Section 6.2.5 Provide a plan for optimizing the use of recycled water in the supplier's service area. N/A (Recycled Water) Section 6.2.6 Describe desalinated water project opportunities for long-term supply. System Supplies Section 6.7 Describe the wastewater collection and treatment systems in the supplier’s service area with System Supplies Section 6.2.5 N/A quantified amount of collection and treatment and the disposal methods. (Recycled Water) Describe the expected future water supply projects and programs that may be undertaken by the Section 6.2.8, water supplier to address water supply reliability in average, single-dry, and for a period of System Supplies Section 6.8 Section 6.3.7 drought lasting 5 consecutive water years. Section 6.4 The UWMP must include energy information, as stated in the code, that a supplier can readily System Suppliers, and Appendix Section 6.10 obtain. Energy Intensity O Provide information on the quality of existing sources of water available to the supplier and the Water Supply Reliability Section 7.2 Chapter 6 manner in which water quality affects water management strategies and supply reliability Assessment Describe water management tools and options to maximize resources and minimize the need to Water Supply Reliability Section 7.2.4 Chapter 6 import water from other regions. Assessment Service Reliability Assessment: Assess the water supply reliability during normal, dry, and a Water Supply Reliability Section 7.3 drought lasting five consecutive water years by comparing the total water supply sources Section 7.1 Assessment available to the water supplier with the total projected water use over the next 20 years. Provide a drought risk assessment as part of information considered in developing the demand Water Supply Reliability Section 7.3 Section 7.2 management measures and water supply projects. Assessment Include a description of the data, methodology, and basis for one or more supply shortage Water Supply Reliability Section 7.3 conditions that are necessary to conduct a drought risk assessment for a drought period that Section 7.2 Assessment lasts 5 consecutive years. Include a determination of the reliability of each source of supply under a variety of water Water Supply Reliability Section 7.3 Section 7.1 shortage conditions. Assessment Include a comparison of the total water supply sources available to the water supplier with the Water Supply Reliability Section 7.3 Section 7.1 total projected water use for the drought period. Assessment

A-3 AVEK 2020 UWMP Appendix A - DWR UWMP Checklist

2020 2020 UWMP Guidebook Summary as Applies to UWMP Subject Location Location Include considerations of the historical drought hydrology, plausible changes on projected Water Supply Reliability Section 7.3 supplies and demands under climate change conditions, anticipated regulatory changes, and Section 7.1 Assessment other locally applicable criteria. Water Shortage Chapter 8 Provide a water shortage contingency plan (WSCP) with specified elements below. Appendix H Contingency Planning Water Shortage Appendix H Chapter 8 Provide the analysis of water supply reliability (from Chapter 7 of Guidebook) in the WSCP Contingency Planning Section 1.1 Describe reevaluation and improvement procedures for monitoring and evaluation the water Water Shortage Appendix H Section 8.10 shortage contingency plan to ensure risk tolerance is adequate and appropriate water shortage Contingency Planning Section 1.8 mitigation strategies are implemented. Provide the written decision-making process and other methods that the supplier will use each Water Shortage Appendix H Section 8.2 year to determine its water reliability. Contingency Planning Section 1.2 Provide data and methodology to evaluate the supplier’s water reliability for the current year and Water Shortage Appendix H Section 8.2 one dry year pursuant to factors in the code. Contingency Planning Section 1.1 Define six standard water shortage levels of 10, 20, 30, 40, 50 percent shortage and greater than 50 percent shortage. These levels shall be based on supply conditions, including percent Water Shortage Appendix H Section 8.3 reductions in supply, changes in groundwater levels, changes in surface elevation, or other Contingency Planning Section 1.3 conditions. The shortage levels shall also apply to a catastrophic interruption of supply. Suppliers with an existing water shortage contingency plan that uses different water shortage Water Shortage Appendix H Section 8.3 levels must cross reference their categories with the six standard categories. Contingency Planning Section 1.3 Suppliers with water shortage contingency plans that align with the defined shortage levels must Water Shortage Appendix H Section 8.4 specify locally appropriate supply augmentation actions. Contingency Planning Section 1.4 Water Shortage Appendix H Section 8.4 Specify locally appropriate demand reduction actions to adequately respond to shortages. Contingency Planning Section 1.4 Water Shortage Appendix H Section 8.4 Specify locally appropriate operational changes. Contingency Planning Section 1.4 Specify additional mandatory prohibitions against specific water use practices that are in addition Water Shortage Appendix H Section 8.4 to state-mandated prohibitions are appropriate to local conditions. Contingency Planning Section 1.4 Estimate the extent to which the gap between supplies and demand will be reduced by Water Shortage Appendix H Section 8.4 implementation of the action. Contingency Planning Section 1.4 Water Shortage Appendix H Section 8.4.6 The plan shall include a seismic risk assessment and mitigation plan. Contingency Plan Section 1.4 Suppliers must describe that they will inform customers, the public and others regarding any Water Shortage Appendix H Section 8.5 current or predicted water shortages. Contingency Planning Section 1.5

A-4 AVEK 2020 UWMP Appendix A - DWR UWMP Checklist

2020 2020 UWMP Guidebook Summary as Applies to UWMP Subject Location Location Suppliers must describe that they will inform customers, the public and others regarding any Section 8.5 Water Shortage Appendix H shortage response actions triggered or anticipated to be triggered and other relevant and 8.6 Contingency Planning Section 1.5 communications. Provide a statement that the supplier will declare a water shortage emergency Water Code Water Shortage Appendix H Section 8.7 Chapter 3. Contingency Planning Section 1.6 Provide a statement that the supplier will coordinate with any city or county within which it Water Shortage Appendix H Section 8.7 provides water for the possible proclamation of a local emergency. Contingency Planning Section 1.6 Describe the potential revenue reductions and expense increases associated with activated Water Shortage Appendix H Section 8.8 shortage response actions. Contingency Planning Section 1.7 Provide a description of mitigation actions needed to address revenue reductions and expense Water Shortage Appendix H Section 8.8 increases associated with activated shortage response actions. Contingency Planning Section 1.7 Provide supporting documentation that Water Shortage Contingency Plan has been, or will be, Sections 8.12 Plan Adoption, Submittal, Appendix H provided to any city or county within which it provides water, no later than 30 days after the and 10.4 and Implementation Section 1.9 submission of the plan to DWR. Make available the Water Shortage Contingency Plan to customers and any city or county where Water Shortage Appendix H Section 8.14 it provides water within 30 after adopted the plan. Contingency Planning Section 1.9 Sections 9.1 Wholesale suppliers shall describe specific demand management measures listed in code, their Demand Management Chapter 9 and 9.3 distribution system asset management program, and supplier assistance program. Measures Notify, at least 60 days prior to the public hearing, any city or county within which the supplier Plan Adoption, Submittal, DWR Table Section 10.2.1 provides water that the urban water supplier will be reviewing the plan and considering and Implementation 10-1 amendments or changes to the plan. Reported in Table 10-1. Each urban water supplier shall update and submit its 2020 plan to the department by July 1, Plan Adoption, Submittal, Section 10.4 Section 10.3 2021. and Implementation Sections Provide supporting documentation that the urban water supplier made the plan and contingency Plan Adoption, Submittal, 10.2.2, 10.3, plan available for public inspection, published notice of the public hearing, and held a public Section 10.2 and Implementation and 10.5 hearing about the plan and contingency plan. The water supplier is to provide the time and place of the hearing to any city or county within Plan Adoption, Submittal, Section 10.2.2 Section 10.1 which the supplier provides water. and Implementation

Provide supporting documentation that the plan and contingency plan has been adopted as Plan Adoption, Submittal, Section 10.3.2 Appendix D prepared or modified. and Implementation

Provide supporting documentation that the urban water supplier has submitted this UWMP to the Plan Adoption, Submittal, Section 10.4 Section 10.3 California State Library. and Implementation

A-5 AVEK 2020 UWMP Appendix A - DWR UWMP Checklist

2020 2020 UWMP Guidebook Summary as Applies to UWMP Subject Location Location Provide supporting documentation that the urban water supplier has submitted this UWMP to any Plan Adoption, Submittal, Section 10.4 Section 10.3 city or county within which the supplier provides water no later than 30 days after adoption. and Implementation Sections The plan, or amendments to the plan, submitted to the department shall be submitted Plan Adoption, Submittal, 10.4.1 and N/A electronically. and Implementation 10.4.2 Provide supporting documentation that, not later than 30 days after filing a copy of its plan with Plan Adoption, Submittal, Section 10.5 the department, the supplier has or will make the plan available for public review during normal Section 10.3 and Implementation business hours. Provide supporting documentation that, not later than 30 days after filing a copy of its water Plan Adoption, Submittal, Section 10.5 shortage contingency plan with the department, the supplier has or will make the plan available Section 10.3 and Implementation for public review during normal business hours. If supplier is regulated by the Public Utilities Commission, include its plan and contingency plan Plan Adoption, Submittal, Section 10.6 N/A as part of its general rate case filings. and Implementation

If revised, submit a copy of the water shortage contingency plan to DWR within 30 days of Plan Adoption, Submittal, Section 10.7.2 N/A adoption. and Implementation

A-6

B

Appendix B: 2020 UWMP DWR Tables

Antelope Valley-East Kern Water Agency 2020 Urban Water Management Plan May 2021 B DRAFT

AVEK 2020 UWMP Appendix B - 2020 UWMP DWR Tables 2-2 | Public Water Systems

Member of Member of Name of RUWMP or Type of Plan RUWMP Regional Alliance Regional Alliance

Individual UWMP No No NA

B-1

AVEK 2020 UWMP Appendix B - 2020 UWMP DWR Tables 2-3 | Agency Identification

Type of Supplier Year Type First Day of Year Unit Type

DD MM Wholesaler Calendar Years Acre Feet (AF)

Conversion to Gallons: 325851 Conversion to Gallons per Day: 892.7425

B-2

AVEK 2020 UWMP Appendix B - 2020 UWMP DWR Tables 2-4W | Water Supplier Information Exchange

Supplier has informed more than 10 other water suppliers of water supplies available in accordance with Water Code Section 10631. Completion of the table below is optional. If not completed, include a list of the water suppliers that were informed. Location of List: Section 2.3.1

B-3

AVEK 2020 UWMP Appendix B - 2020 UWMP DWR Tables 3-1W | Current & Projected Population - -

Population Served 2020 2025 2030 2035 2040 2045

Los Angeles and 270,615 288,578 306,542 324,505 342,229 359,953 Ventura Counties Kern County 49,956 56,757 63,558 70,359 78,738 87,118

Total 320,571 345,335 370,100 394,864 420,967 447,071

Notes: 1. Data for Los Angeles and Ventura Counties from SCAG 2020 Connect SoCal Regional Transportation Plan (SCAG, 2020) 2. Data for Kern County from KCOG General Land Use Plan (KCOG, 2018a).

B-4

AVEK 2020 UWMP Appendix B - 2020 UWMP DWR Tables 4-1W | Actual Demands for Water - - - - - Additional Level of Treatment 2020 Use Type Description When Delivered Volume Sales/Transfers/Exchanges to Los Angeles County Drinking Water 32,847 Other Agencies Waterworks District Sales/Transfers/Exchanges to Quartz Hill Water Drinking Water 2,533 Other Agencies District Sales/Transfers/Exchanges to Rio Tinto Minerals / US Drinking Water 1,503 Other Agencies Borax Sales/Transfers/Exchanges to Edwards Air Force Drinking Water 1,465 Other Agencies Base Sales/Transfers/Exchanges to Other M&I Customers Drinking Water 2,095 Other Agencies (19 Customers) Sales/Transfers/Exchanges to Raw Water Deliveries Raw Water 837 Other Agencies (4 Customers) Sales/Transfers/Exchanges to Transfers to Other Raw Water 11,286 Other Agencies Agencies Groundwater Recharge Groundwater Recharge Raw Water 7,213 Losses Losses Drinking Water 457

- Total: 60,234

Source: AVEK, 2020 LATIS data

B-5

AVEK 2020 UWMP Appendix B - 2020 UWMP DWR Tables 4-2W | Projected Demands for Water ------Projected Water Use Use Type Additional Description 2025 2030 2035 2040 2045

Sales/Transfers/Exchanges to 44,440 50,990 51,880 55,210 57,590 Other Agencies

- Total: 44,440 50,990 51,880 55,210 57,590

B-6

AVEK 2020 UWMP Appendix B - 2020 UWMP DWR Tables 4-3W | Total Water Use - -

- 2020 2025 2030 2035 2040 2045

Potable and Raw Water 60,234 44,440 44,440 44,440 44,440 44,440 From Table 4-1W and 4-2W

Recycled Water Demand* ------From Table 6-4W

Total Water Demand: 60,234 44,440 44,440 44,440 44,440 44,440

-

B-7

AVEK 2020 UWMP Appendix B - 2020 UWMP DWR Tables 6-1W | Groundwater Volume Pumped - - Select One

Groundwater Type Location or Basin Name 2016 2017 2018 2019 2020

Alluvial Basin AV Basin, Production Rights - - - - - Alluvial Basin AV Basin, Banking 11,512 7,868 9,162 9,234 12,228

- Total: 11,512 7,868 9,162 9,234 12,228

B-8

AVEK 2020 UWMP Appendix B - 2020 UWMP DWR Tables 6-3W | Wastewater Treatment & Discharge Within Service Area in 2020 - - Wholesale Supplier neither distributes nor provides supplemental treatment to recycled water. The supplier will not complete the table. - 2020 Volumes Wastewater Discharge Location Discharge Location Wastewater Method of Plant Treats Treatment Level Discharged Recycled Recycled Instream Flow Treatment Plant Name or Identifier Description Discharge ID Disposal Wastewater Wastewater Treated Within Service Outside of Permit Name Number Generated Outside Treated the Service Area Wastewater Area Service Area Requirement

- Total: - - - - -

-

B-9

AVEK 2020 UWMP Appendix B - 2020 UWMP DWR Tables 6-4W | Current & Projected Retailers Provided Recycled Water within Service Area - -

Recycled water is not used and is not planned for use within the service area of the supplier. The supplier will not complete the table.

B-10

AVEK 2020 UWMP Appendix B - 2020 UWMP DWR Tables 6-5W | 2015 Recycled Water Use Projection Compared to 2020 Actual - - - - Recycled water was not used or distributed by the supplier in 2015, nor projected for use or distribution in 2020. The supplier will not complete the table. - -

B-11

AVEK 2020 UWMP Appendix B - 2020 UWMP DWR Tables 6-7W | Expected Future Water Supply Projects or Programs - - Some or all of the supplier's future water supply projects or programs are not compatible with this table and are described in a narrative format.

- Page Location for Narrative in UWMP: Section 6.8

Joint Project Planned Expected Increase Name of Future Planned for Use in with Other Agency Name Description Implementation in Water Supply to Projects or Programs Year Type Suppliers Year Supplier

Note: Refer to 2020 UWMP Section 6.8

B-12

AVEK 2020 UWMP Appendix B - 2020 UWMP DWR Tables 6-8W | Actual Water Supplies - - - 2020 Actual Total Right or Safe Water Supply Additional Detail on Water Supply Water Quality Volume Yield Purchased or Imported Water To Retailers - Treated Water 28,732 Drinking Water Other Non-Potable Purchased or Imported Water To Retailers - Untreated Water 775 Water Other Non-Potable Purchased or Imported Water To GW Bank - Untreated Water 7,213 Water Groundwater (not desalinated) From GW Bank - Treated Water 12,228 Drinking Water Transfer / Exchanges - Untreated Other Non-Potable Purchased or Imported Water 11,286 Water Water

- Total: 60,234 -

B-13

AVEK 2020 UWMP Appendix B - 2020 UWMP DWR Tables 6-8DS | Source Water Desalination - - - -

Neither groundwater nor surface water are reduced in salinity prior to distribution. The supplier will not complete the table.

- -

B-14

AVEK 2020 UWMP Appendix B - 2020 UWMP DWR Tables 6-9W | Projected Water Supplies - - - - - Projected Water Supply - 2025 2030 2035 2040 2045 Reasonably Reasonably Reasonably Reasonably Reasonably Additional Detail on Water Total Right or Total Right or Total Right or Total Right or Total Right or Water Supply Available Available Available Available Available Supply Safe Yield Safe Yield Safe Yield Safe Yield Safe Yield Volume Volume Volume Volume Volume Purchased or Imported Water SWP Table A 81,840 79,660 77,490 75,320 75,320 Groundwater (not desalinated) Production Rights 3,550 3,550 3,550 3,550 3,550 Imported Water Return Groundwater (not desalinated) 800 800 800 800 800 Flows Purchased or Imported Water New LACWWD Supply 4,890 9,780 12,190 14,760 17,340

- Total: 91,080 - 93,790 - 94,030 - 94,430 - 97,010 -

B-15

AVEK 2020 UWMP Appendix B - 2020 UWMP DWR Tables

7-1W | Basis of Water Year Data (Reliability Assessment) - - - - Quantification of available supplies is not compatible with this table and is provided elsewhere in the UWMP.

Page Location for Narrative in UWMP: Page 7-2

B-16

AVEK 2020 UWMP Appendix B - 2020 UWMP DWR Tables 7-2W | Normal Year Supply and Demand Comparison - - - -

2025 2030 2035 2040 2045 - Supply Totals 91,080 93,790 94,030 94,430 97,010 From Table 6-9W

Demand Totals 44,440 44,440 44,440 44,440 44,440 From Table 4-3W

Difference: 46,640 49,350 49,590 49,990 52,570

- -

B-17

AVEK 2020 UWMP Appendix B - 2020 UWMP DWR Tables 7-3W | Single Dry Year Supply & Demand Comparison - - - -

2025 2030 2035 2040 2045 -

Supply Totals 44,440 50,990 51,880 55,210 57,590

Demand Totals 44,440 50,990 51,880 55,210 57,590

Difference: 0 0 0 0 0

Note: Supply equals demand because AVEK would extract groundwater stored in local groundwater banks to meet supply shortfalls.

- -

B-18

AVEK 2020 UWMP Appendix B - 2020 UWMP DWR Tables 7-4W | Multiple Dry Years Supply & Demand Comparison ------

- - 2025 2030 2035 2040 2045

Supply Totals 44,440 50,990 51,880 55,210 57,590 First Year Demand Totals 44,440 50,990 51,880 55,210 57,590

- Difference: 0 0 0 0 0

Supply Totals 53,820 56,760 58,370 60,180 61,780 Second Year Demand Totals 44,440 50,990 51,880 55,210 57,590

- Difference: 9,380 5,770 6,490 4,970 4,190

Supply Totals 44,440 50,990 51,880 55,210 57,590 Third Year Demand Totals 44,440 50,990 51,880 55,210 57,590

- Difference: 0 0 0 0 0

Supply Totals 44,440 50,990 51,880 55,210 57,590 Fourth Year Demand Totals 44,440 50,990 51,880 55,210 57,590

- Difference: 0 0 0 0 0

Supply Totals 44,440 50,990 51,880 55,210 57,590 Fifth Year Demand Totals 44,440 50,990 51,880 55,210 57,590

- Difference: 0 0 0 0 0

Supply Totals Sixth Year Demand Totals

- Difference: 0 0 0 0 0 Note: Supply equals demand because AVEK would extract groundwater stored in local groundwater banks to meet supply shortfalls.

- - -

B-19

AVEK 2020 UWMP Appendix B - 2020 UWMP DWR Tables 7-5 | Five-Year Drought Risk Assessment Tables to Address Water Code Section 10635(b) - - -

Gross Water Use 39,060 Total Supplies 22,590 Surplus/Shortfall without WSCP Action -16,470 Planned WSCP Actions (Use Reduction and Supply Augmentation) 2021 WSCP (Supply Augmentation Benefit) 16,470 WSCP (Use Reduction Savings Benefit) Revised Surplus/Shortfall 0 Resulting Percent Use Reduction from WSCP Action 0% Gross Water Use 40,930 Total Supplies 52,280 Surplus/Shortfall without WSCP Action 11,350 Planned WSCP Actions (Use Reduction and Supply Augmentation) 2022 WSCP (Supply Augmentation Benefit) WSCP (Use Reduction Savings Benefit) Revised Surplus/Shortfall 11,350 Resulting Percent Use Reduction from WSCP Action 0% Gross Water Use 42,590 Total Supplies 24,400 Surplus/Shortfall without WSCP Action -18,190 Planned WSCP Actions (Use Reduction and Supply Augmentation) 2023 WSCP (Supply Augmentation Benefit) 18,190 WSCP (Use Reduction Savings Benefit) Revised Surplus/Shortfall 0 Resulting Percent Use Reduction from WSCP Action 0% Gross Water Use 43,340 Total Supplies 43,180 Surplus/Shortfall without WSCP Action -160 Planned WSCP Actions (Use Reduction and Supply Augmentation) 2024 WSCP (Supply Augmentation Benefit) 160 WSCP (Use Reduction Savings Benefit) Revised Surplus/Shortfall 0 Resulting Percent Use Reduction from WSCP Action 0% Gross Water Use 44,440 Total Supplies 31,960 Surplus/Shortfall without WSCP Action -12,480 Planned WSCP Actions (Use Reduction and Supply Augmentation) 2025 WSCP (Supply Augmentation Benefit) 12,480 WSCP (Use Reduction Savings Benefit) Revised Surplus/Shortfall 0 Resulting Percent Use Reduction from WSCP Action 0% WSCP (Supply Augmentation Benefit) is AVEK pumping from its local groundwater banks

B-20

AVEK 2020 UWMP Appendix B - 2020 UWMP DWR Tables 8-1 | Water Shortage Contingency Plan Levels - - - - - Shortage Percent Shortage Range1 Shortage Response Actions Level (Numerical Value as a Percent) 1 Up to 50% Reduction in SWP Allocation below Current Demand 2 >50% Catastrophic water supply shortage 1 One stage in the Water Shortage Contingency Plan must address a water shortage of 50%.

- -

B-21

AVEK 2020 UWMP Appendix B - 2020 UWMP DWR Tables 8-2 | Demand Reduction Actions - - - - - How much is Penalty, this going to Additional Shortage Charge, or Demand Reduction Actions reduce the Explanation Level Other shortage or Reference Enforcement gap? All Expand Public Information Campaign up to 50% - -

B-22

AVEK 2020 UWMP Appendix B - 2020 UWMP DWR Tables 8-3 | Supply Augmentation & Other Actions - - - - - How much is this Additional Shortage Supply Augmentation Methods and Other Actions by Water Supplier going to reduce the Explanation or Level shortage gap? Reference - -

B-23

AVEK 2020 UWMP Appendix B - 2020 UWMP DWR Tables 10-1W | Notification to Cities & Counties ------

Supplier has not notified more than 10 cities or counties in accordance with Water Code Sections 10621 (b) and 10642. Completion of the table is required.

City 60 Day Notice Notice of Public Hearing Other

City of California City Yes Yes City of Lancaster Yes Yes City of Palmdale Yes Yes

County 60 Day Notice Notice of Public Hearing Other

Kern County Yes Yes Los Angeles County Yes Yes Ventura County Yes Yes

Other 60 Day Notice Notice of Public Hearing Other

Note: See Appendix D for notices.

- -

B-24

C

Appendix C: Delta Reliance

Antelope Valley-East Kern Water Agency 2020 Urban Water Management Plan May 2021 C DRAFT Appendix C - Delta Reliance Technical Memorandum DRAFT

Date: 5/25/2021

To: Matt Knudson Antelope Valley – East Kern Water Agency (AVEK)

CC: Tom Barnes (AVEK)

Prepared by: Rob Morrow, P.E.

Project: 2020 UWMP

SUBJECT: QUANTIFYING REGIONAL SELF-RELIANCE AND REDUCED RELIANCE ON WATER SUPPLIES FROM THE DELTA WATERSHED

1 Background Under the Sacramento-San Joaquin Delta Reform Act of 2009, state and local public agencies proposing a covered action in the Delta, prior to initiating the implementation of that action, must prepare a written certification of consistency with detailed findings as to whether the covered action is consistent with applicable Delta Plan policies and submit that certification to the Delta Stewardship Council. Anyone may appeal a certification of consistency, and if the Delta Stewardship Council grants the appeal, the covered action may not be implemented until the agency proposing the covered action submits a revised certification of consistency, and either no appeal is filed, or the Delta Stewardship Council denies the subsequent appeal.

An urban water supplier that anticipates participating in or receiving water from a proposed covered action such as a multi-year water transfer, conveyance facility, or new diversion that involves transferring water through, exporting water from, or using water in the Delta should provide information in their 2015 and 2020 Urban Water Management Plans (UWMPs) that can then be used in the covered action process to demonstrate consistency with Delta Plan Policy WR P1, Reduce Reliance on the Delta Through Improved Regional Water Self-Reliance (WR P1).

WR P1 details what is needed for a covered action to demonstrate consistency with reduced reliance on the Delta and improved regional self-reliance. WR P1 subsection (a) states that: (a) Water shall not be exported from, transferred through, or used in the Delta if all of the following apply: (1) One or more water suppliers that would receive water as a result of the export, transfer, or use have failed to adequately contribute to reduced reliance on the Delta and improved regional self- reliance consistent with all of the requirements listed in paragraph (1) of subsection (c); (2) That failure has significantly caused the need for the export, transfer, or use; and (3) The export, transfer, or use would have a significant adverse environmental impact in the Delta.

App C - Delta Reliance_DRAFT_05-25 Appendix C - Delta Reliance AVEK 2020 UWMP DRAFT Quantifying Regional Self-Reliance and Reduced Reliance on Water Supplies from the Delta Watershed

WR P1 subsection (c)(1) further defines what adequately contributing to reduced reliance on the Delta means in terms of (a)(1) above. (c)(1) Water suppliers that have done all the following are contributing to reduced reliance on the Delta and improved regional self-reliance and are therefore consistent with this policy: (A) Completed a current Urban or Agricultural Water Management Plan (Plan) which has been reviewed by the California Department of Water Resources for compliance with the applicable requirements of Water Code Division 6, Parts 2.55, 2.6, and 2.8; (B) Identified, evaluated, and commenced implementation, consistent with the implementation schedule set forth in the Plan, of all programs and projects included in the Plan that are locally cost effective and technically feasible which reduce reliance on the Delta; and (C) Included in the Plan, commencing in 2015, the expected outcome for measurable reduction in Delta reliance and improvement in regional self-reliance. The expected outcome for measurable reduction in Delta reliance and improvement in regional self- reliance shall be reported in the Plan as the reduction in the amount of water used, or in the percentage of water used, from the Delta watershed. For the purposes of reporting, water efficiency is considered a new source of water supply, consistent with Water Code section 1011(a). The analysis and documentation provided below include all the elements described in WR P1(c)(1) that need to be included in a water supplier’s UWMP to support a certification of consistency for a future covered action.

2 Methodology As stated in WR P1(c)(1)(C), the policy requires that, commencing in 2015, UWMPs include expected outcomes for improved regional self-reliance and measurable reduction in Delta reliance. WR P1 further states that those outcomes shall be reported in the UWMP as the reduction in the amount of water used, or in the percentage of water used, from the Delta. The expected outcomes for AVEK regional self-reliance and reduced Delta reliance were developed using the approach and guidance described in Appendix C of DWR’s Urban Water Management Plan Guidebook 2020 issued in March 2020 (Guidebook Appendix C).

The methodology used to determine AVEK’s improved regional self-reliance and reduced Delta reliance is consistent with the approach detailed in DWR’s UWMP Guidebook Appendix C, including the use of narrative justifications for the accounting of supplies and the documentation of specific data sources. Some of the key assumptions include:

• All data were obtained from the current 2020 UWMP or previously adopted UWMPs and represent average or normal water year conditions. • All analyses were conducted at the service area level, and all data reflect the total contributions of AVEK and its customers as well as their customers.

To calculate the expected outcomes for improved regional self-reliance and reduced Delta reliance, a baseline is needed to compare against. This analysis uses a normal water year representation of 2010 as the baseline, which is consistent with the approach described in the Guidebook Appendix C. Data for the 2010 baseline were taken

5/25/2021 2

App C - Delta Reliance_DRAFT_05-25 Appendix C - Delta Reliance AVEK 2020 UWMP DRAFT Quantifying Regional Self-Reliance and Reduced Reliance on Water Supplies from the Delta Watershed from AVEK’s 2005 UWMP as the UWMPs generally do not provide normal water year data for the year that they are adopted (i.e., 2005 UWMP forecasts begin in 2010, 2010 UWMP forecasts begin in 2015, and so on).

Consistent with the 2010 baseline data approach, the expected outcomes for improved regional self-reliance and reduced Delta reliance for 2015 and 2020 were taken from AVEK’s 2010 and 2015 UWMPs, respectively. Expected outcomes for 2025-2045 are from the current 2020 UWMP. Documentation of the specific data sources and assumptions are included in the discussions below.

3 Demonstration of Regional Self-Reliance Service Area Demands without Water Use Efficiency In alignment with the Guidebook Appendix C, this analysis uses normal water year demands, rather than normal water year supplies to calculate expected outcomes in terms of the percentage of water used. Using normal water year demands serves as a proxy for the amount of supplies that would be used in a normal water year, which helps alleviate issues associated with how supply capability is presented to fulfill requirements of the UWMP Act versus how supplies might be accounted for to demonstrate consistency with WR P1.

Because WR P1 considers water use efficiency savings a source of water supply, water suppliers such as AVEK that do not explicitly quantify water use efficiency savings in their UWMPs can calculate their embedded water use efficiency savings based on changes in forecasted per capita water use since the baseline.

Agencies that explicitly calculate and report water use efficiency savings in their UWMP will need to make an adjustment to properly reflect normal water year demands in the calculation of reduced reliance. As explained in the Guidebook Appendix C, water use efficiency savings must be added back to the normal year demands to represent demands without water use efficiency savings accounted for; otherwise the effect of water use efficiency savings on regional self-reliance would be overestimated. Table 1 shows the results of this adjustment for AVEK. Supporting narratives and documentation for all the data shown in Table 1 are provided below.

Service Area Demands with Water Use Efficiency

The service area demands shown in Table 1 represent the total water demands for AVEK’s service area. The demand data shown in Table 1 were collected from the following sources:

• Baseline (2010): AVEK 2005 UWMP, Table 7 and Table 8 • 2015: AVEK 2010 UWMP, Table 4 and Table 5 • 2020: AVEK 2015 UWMP, Table 4-2 • 2025-2045: AVEK 2020 UWMP, Table ES-2

Service Area Population

The population data shown in Table 1 were collected from the following sources:

• Baseline (2010): AVEK 2010 UWMP, Table 2 • 2015: AVEK 2015 UWMP, Table 3-1 • 2020-2045: AVEK 2020 UWMP, Table ES-1

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App C - Delta Reliance_DRAFT_05-25 Appendix C - Delta Reliance AVEK 2020 UWMP DRAFT Quantifying Regional Self-Reliance and Reduced Reliance on Water Supplies from the Delta Watershed

Estimated Water Use Efficiency Since Baseline

Calculated using “Potable Service Area Demands with Water Use Efficiency” divided by “Service Area Population” and then calculating Estimated Water Use Efficiency Since Baseline by comparing with 2010 Per Capita Water Use.

Service Area Water Demands without Water Use Efficiency

Add “Service Area Demands with Water Use Efficiency” to “Estimated Water Use Efficiency Since Baseline.”

Supplies Contributing to Regional Self-Reliance For a covered action to demonstrate consistency with the Delta Plan, WR P1 subsection (c)(1)(C) states that water suppliers must report the expected outcomes for measurable improvement in regional self-reliance. Table 2 shows expected outcomes for supplies contributing to regional self-reliance both in amount and as a percentage. The numbers shown in Table 2 represent efforts to improve regional self-reliance for AVEK’s entire service area and include the total contributions of AVEK and its customers. Supporting narratives and documentation for all of the data shown in Table 2 are provided below.

Water Use Efficiency

The water use efficiency information shown in Table 2 is taken directly from Table 1.

Local and Regional Water Supply and Storage Programs

The local and regional water supply and storage programs data shown in Table 2 represent groundwater pumping estimates by AVEK and entities within AVEK’s service area. The estimates were complicated because the Antelope Valley Groundwater Basin Judgment (Judgment) did not go into effect until 2016 and roughly half of annual pumping rights are associated with imported water return flows, which is dependent on total demands in the AVEK service area. Now that the Judgment is in place, the following categories were totaled to estimate annual pumping rights

• Exhibit 3 – Non-Overlying Producers Production Rights o Production Rights o Rights from Return Flows • Exhibit 4 – Overlying Producers Production Rights o Production Rights o Rights from Return Flows Based on this information, groundwater pumping data was estimated from the following sources:

• Baseline (2010): Prior to the Judgement, there were not estimates of groundwater pumping within AVEK service area so the 2010 pumping value was assumed to be equivalent to the 2015 estimate • 2015: Groundwater accounting for the Judgement started in 2016 so the 2016 production rights values for 2016 from the 2016 Annual Report from the Antelope Valley Watermaster were used for 2015 values • 2020: 2020 groundwater sources from the Annual Report from the Antelope Valley Watermaster • 2025-2045: Judgement production rights plus estimated return flows based on projected AVEK demands presented in the 2020 UWMP

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App C - Delta Reliance_DRAFT_05-25 Appendix C - Delta Reliance AVEK 2020 UWMP DRAFT Quantifying Regional Self-Reliance and Reduced Reliance on Water Supplies from the Delta Watershed

Conclusions The results shown in Table 2 demonstrate that AVEK’s service area is measurably improving its regional self- reliance. In the near-term (2025), the expected outcome for normal water year regional self-reliance is expected to increase by 55,800 AFY from the 2010 baseline; this represents an increase of about 37 percent of 2025 normal water year retail demands. In the long-term (2045), the expected outcome for normal water year regional self- reliance is expected to increase by more than 81,400 AFY from the 2010 baseline, this represents an increase of about 37 percent of 2045 normal water year retail demands (Table 2). The results show that as a region, AVEK and its customers are measurably reducing reliance on the Delta and improving regional self-reliance, both as an amount of water used and as a percentage of water used.

4 Demonstration of Reduced Reliance on the Delta AVEK’s service area reduces reliance on the Delta through investments in non-Delta water supplies, local water supplies, and regional and local demand management measures. For reduced reliance on supplies from the Delta Watershed, the data used in this analysis represent the total regional efforts of AVEK and its customers, and were developed in conjunction with AVEK customers as part of the UWMP coordination process (as described in Chapter 2 of AVEK’s 2020 UWMP). In accordance with UMWP requirements, several of AVEK’s customers also report demands and supplies for their service areas in their respective UWMPs. The data reported by those agencies are not additive to the regional totals shown in AVEK’s UWMP, rather their reporting represents subtotals of the regional total and should be considered as such for the purposes of determining reduced reliance on the Delta.

Calculation of Reliance on Water Supplies from the Delta Watershed The calculation of reliance on water supplies from the Delta watershed, shown in Table 3, is based on the following assumptions. AVEK water supplies from the Delta watershed include

• CVP/SWP Contract Supplies • Other Water Supplies from the Delta Watershed

CVP/SWP Contract Supplies

The supply data shown in Table 3 is for AVEK’s SWP Table A allocation and were collected from the following sources:

• Baseline (2010): AVEK 2005 UWMP, Table 10 • 2015: AVEK 2010 UWMP, Table 6 • 2020: AVEK 2015 UWMP, Table 6-9 • 2025-2045: AVEK 2020 UWMP, Table ES-3

Other Water Supplies from the Delta Watershed

The supply data shown in Table 3 is for new supplemental water supplies acquired by AVEK for Los Angeles County Waterworks District (LACWD) and is based on AVEK’s 2020 UWMP Section 6.8.1 and Table 6-11.

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App C - Delta Reliance_DRAFT_05-25 Appendix C - Delta Reliance AVEK 2020 UWMP DRAFT Quantifying Regional Self-Reliance and Reduced Reliance on Water Supplies from the Delta Watershed

Change in Supplies from the Delta Watershed

Adds “CVP/SWP Contract Supplies” and “Other Water Supplies from the Delta Watershed” to get total Water Supplies from the Delta Watershed and calculates changes from the 2010 baseline.

Percent Change in Supplies from the Delta Watershed

Divides “Water Supplies from the Delta Watershed” by “Service Area Demands without Water Use Efficiency” and calculates changes from the 2010 baseline.

Conclusions The following provides a summary of the near-term (2025) and long-term (2045) expected outcomes for AVEK’s Delta reliance on supplies from the Delta watershed:

• Near-term (2025) – Normal water year reliance on supplies from the Delta watershed decreased by 13,700 AF from the 2010 baseline, this represents a decrease of 25 percent of 2025 normal water year demands without water use efficiency (Table 3). • Long-term (2045) – Normal water year reliance on supplies from the Delta watershed decreased by 7,700 AF from the 2010 baseline, this represents a decrease of 36 percent of 2025 normal water year demands without water use efficiency (Table 3).

The results show that as a region, AVEK and its customers (including AVEK) as well as their customers are measurably reducing reliance on the Delta and improving regional self-reliance, both as an amount of water used and as a percentage of water used.

5 UWMP Implementation In addition to the analysis and documentation described above, WR P1 subsection (c)(1)(B) requires that all programs and projects included in the UWMP that are locally cost-effective and technically feasible, which reduce reliance on the Delta, are identified, evaluated, and implemented consistent with the implementation schedule. WR P1 (c)(1)(B) states that:

(B) Identified, evaluated, and commenced implementation, consistent with the implementation schedule set forth in the Plan, of all programs and projects included in the Plan that are locally cost effective and technically feasible which reduce reliance on the Delta[.]

In accordance with Water Code Section 10631(f), water suppliers must already include in their UWMP a detailed description of expected future projects and programs that they may implement to increase the amount of water supply available to them in normal and single-dry water years and for a period of drought lasting five consecutive years. The UWMP description must also identify specific projects, include a description of the increase in water supply that is expected to be available from each project, and include an estimate regarding the implementation timeline for each project or program.

Chapter 6 of AVEK’s 2020 UWMP summarizes the implementation plan and continued progress in developing a diversified water portfolio to meet the region’s water needs.

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App C - Delta Reliance_DRAFT_05-25 Appendix C - Delta Reliance AVEK 2020 UWMP DRAFT Quantifying Regional Self-Reliance and Reduced Reliance on Water Supplies from the Delta Watershed

6 2015 UWMP Appendix J The information contained in this appendix is also intended to be a new Appendix J attached to AVEK’s 2015 UWMP consistent with WR P1 subsection (c)(1)(C) (Cal. Code Regs. tit. 23, § 5003). AVEK provided notice of the availability of the draft 2020 UWMP, 2021 WSCP, and a new Appendix J to the 2015 UWMP and the public hearing to consider adoption of the documents in accordance with CWC Sections 10621(b) and 10642, and Government Code Section 6066, and Chapter 17.5 (starting with Section 7290) of Division 7 of Title 1 of the Government Code. The public review drafts of the 2020 UWMP, Appendix J to the 2015 UWMP, and the 2021 WSCP were posted on AVEK’s website, avek.org, on April 6, 2021, more than 60 days in advance of the public hearing on June 8, 2021. The notice of availability of the documents was sent to AVEK’s customers, as well as cities and counties in AVEK’s service area. Copies of the notification letter sent to the customers and cities and counties in AVEK’s service area are included in the 2020 UWMP Appendix D. Thus, this Appendix C to AVEK’s 2020 UWMP, which was adopted with AVEK’s 2020 UWMP, will also be recognized and treated as Appendix J to AVEK’s 2015 UWMP.

AVEK held the public hearing for the draft 2020 UWMP, draft Appendix J to the 2015 UWMP, and draft 2021 WSCP on June 8, 2021, at a regular Board of Directors meeting, held online due to COVID-19 concerns. On June 22, 2021, AVEK’s Board of Directors determined that the 2020 UWMP and the 2021 WSCP accurately represent the water resources plan for AVEK’s service area. In addition, AVEK’s Board of Directors determined that Appendix J to both the 2015 UWMP and the 2020 UWMP includes all of the elements described in Delta Plan Policy WR P1, Reduce Reliance on the Delta Through Improved Regional Water Self-Reliance (Cal. Code Regs. tit. 23, § 5003), which need to be included in a water supplier’s UWMP to support a certification of consistency for a future covered action. As stated in Resolutions XXXX, XXXX, and XXXX, the AVEK Board of Directors adopted the 2020 UWMP, Appendix J to the 2015 UWMP, and the 2021 WSCP and authorized their submittal to the State of California. Copies of the resolutions are included in the 2020 UWMP Appendix E.

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App C - Delta Reliance_DRAFT_05-25 Appendix C - Delta Reliance AVEK 2020 UWMP DRAFT Quantifying Regional Self-Reliance and Reduced Reliance on Water Supplies from the Delta Watershed

Table 1. Calculation of Service Area Water Demands without Water Use Efficiency (UWMP Table C-1 and Table C-2)

Table C-1: Optional Calculation of Water Use Efficiency -To be completed if Water Supplier does not specifically estimate Water Use Efficiency as a supply Service Area Water Use Efficiency Demands Baseline 2045 2015 2020 2025 2030 2035 2040 (Acre-Feet) (2010) (Optional) Service Area Water Demands with Water Use Efficiency Accounted For 111,031 91,075 83,680 73,420 80,400 83,850 87,520 91,200 Non-Potable Water Demands Potable Service Area Demands with Water Use Efficiency Accounted For 111,031 91,075 83,680 73,420 80,400 83,850 87,520 91,200

Baseline 2045 Total Service Area Population 2015 2020 2025 2030 2035 2040 (2010) (Optional) Service Area Population 291,063 359,500 320,571 345,335 370,100 394,864 420,967 447,071

Water Use Efficiency Since Baseline Baseline 2045 2015 2020 2025 2030 2035 2040 (Acre-Feet) (2010) (Optional) Per Capita Water Use (GPCD) 341 226 233 190 194 190 186 182 Change in Per Capita Water Use from Baseline (GPCD) (114) (108) (151) (147) (151) (155) (158) Estimated Water Use Efficiency Since Baseline 46,062 38,607 58,314 60,781 66,778 73,065 79,343

Table C-2: Calculation of Service Area Water Demands Without Water Use Efficiency Total Service Area Water Demands Baseline 2045 2015 2020 2025 2030 2035 2040 (Acre-Feet) (2010) (Optional) Service Area Water Demands with Water Use Efficiency Accounted For 111,031 91,075 83,680 73,420 80,400 83,850 87,520 91,200 Reported Water Use Efficiency or Estimated Water Use Efficiency Since Baseline 46,062 38,607 58,314 60,781 66,778 73,065 79,343 Service Area Water Demands without Water Use Efficiency Accounted For 111,031 137,137 122,287 131,734 141,181 150,628 160,585 170,543

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App C - Delta Reliance_DRAFT_05-25 Appendix C - Delta Reliance AVEK 2020 UWMP DRAFT Quantifying Regional Self-Reliance and Reduced Reliance on Water Supplies from the Delta Watershed

Table 2. Calculation of Supplies Contributing to Regional Self-Reliance (UWMP Table C-3)

Table C-3: Calculation of Supplies Contributing to Regional Self-Reliance Water Supplies Contributing to Regional Self-Reliance Baseline 2045 2015 2020 2025 2030 2035 2040 (Acre-Feet) (2010) (Optional) Water Use Efficiency 46,062 38,607 58,314 60,781 66,778 73,065 79,343 Water Recycling Stormwater Capture and Use Advanced Water Technologies Conjunctive Use Projects Local and Regional Water Supply and Storage Projects 35,870 35,870 33,280 33,330 33,760 36,320 36,660 37,960 Other Programs and Projects the Contribute to Regional Self-Reliance Water Supplies Contributing to Regional Self-Reliance 35,870 81,932 71,887 91,644 94,541 103,098 109,725 117,303

Service Area Water Demands without Water Use Efficiency Baseline 2045 2015 2020 2025 2030 2035 2040 (Acre-Feet) (2010) (Optional) Service Area Water Demands without Water Use Efficiency Accounted For 111,031 137,137 122,287 131,734 141,181 150,628 160,585 170,543

Change in Regional Self Reliance Baseline 2045 2015 2020 2025 2030 2035 2040 (Acre-Feet) (2010) (Optional) Water Supplies Contributing to Regional Self-Reliance 35,870 81,932 71,887 91,644 94,541 103,098 109,725 117,303 Change in Water Supplies Contributing to Regional Self-Reliance 46,062 36,017 55,774 58,671 67,228 73,855 81,433 Percent Change in Regional Self Reliance Baseline 2045 2015 2020 2025 2030 2035 2040 (As Percent of Demand w/out WUE) (2010) (Optional) Percent of Water Supplies Contributing to Regional Self-Reliance 32.3% 59.7% 58.8% 69.6% 67.0% 68.4% 68.3% 68.8% Change in Percent of Water Supplies Contributing to Regional Self-Reliance 27.4% 26.5% 37.3% 34.7% 36.1% 36.0% 36.5%

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App C - Delta Reliance_DRAFT_05-25 Appendix C - Delta Reliance AVEK 2020 UWMP DRAFT Quantifying Regional Self-Reliance and Reduced Reliance on Water Supplies from the Delta Watershed

Table 3. Reliance on Water Supplies from the Delta Watershed (UWMP Table C-4)

Table C-4: Calculation of Reliance on Water Supplies from the Delta Watershed Water Supplies from the Delta Watershed Baseline 2045 2015 2020 2025 2030 2035 2040 (Acre-Feet) (2010) (Optional) CVP/SWP Contract Supplies 100,394 87,688 85,460 81,840 79,660 77,490 75,320 75,320 Delta/Delta Tributary Diversions Transfers and Exchanges Other Water Supplies from the Delta Watershed 4,890 9,780 12,190 14,760 17,340 Total Water Supplies from the Delta Watershed 100,394 87,688 85,460 86,730 89,440 89,680 90,080 92,660

Service Area Water Demands without Water Use Efficiency Baseline 2045 2015 2020 2025 2030 2035 2040 (Acre-Feet) (2010) (Optional) Service Area Water Demands without Water Use Efficiency Accounted For 111,031 137,137 122,287 131,734 141,181 150,628 160,585 170,543

Change in Supplies from the Delta Watershed Baseline 2045 2015 2020 2025 2030 2035 2040 (Acre-Feet) (2010) (Optional) Water Supplies from the Delta Watershed 100,394 87,688 85,460 86,730 89,440 89,680 90,080 92,660 Change in Water Supplies from the Delta Watershed (12,706) (14,934) (13,664) (10,954) (10,714) (10,314) (7,734) Percent Change in Supplies from the Delta Watershed Baseline 2045 2015 2020 2025 2030 2035 2040 (As a Percent of Demand w/out WUE) (2010) (Optional) Percent of Water Supplies from the Delta Watershed 90.4% 63.9% 69.9% 65.8% 63.4% 59.5% 56.1% 54.3% Change in Percent of Water Supplies from the Delta Watershed -26.5% -20.5% -24.6% -27.1% -30.9% -34.3% -36.1%

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App C - Delta Reliance_DRAFT_05-25

D

Appendix D: Notifications and Notification List

Antelope Valley-East Kern Water Agency 2020 Urban Water Management Plan May 2021 D DRAFT

AVEK 2020 UWMP Appendix D - Notifications

April 6, 2021

NOTICE OF PUBLIC HEARING ON THE ANTELOPE VALLEY‐EAST KERN WATER AGENCY DRAFT 2020 URBAN WATER MANAGEMENT PLAN, DRAFT 2021 WATER SHORTAGE CONTINGENCY PLAN, AND DRAFT APPENDIX J TO THE 2015 UWMP

Dear Recipient,

The Antelope Valley‐East Kern Water Agency (AVEK) is in the process of preparing its 2020 Urban Water Management Plan (UWMP) and 2021 Water Shortage Contingency Plan (WSCP) as required by the Urban Water Management Planning Act (Act). In addition, AVEK is preparing an Appendix to both the 2015 UWMP and 2020 UWMP to demonstrate consistency with the Delta Plan Policy WR P1, Reduced Reliance on the Delta Through Improved Regional Water Self‐Reliance (California Code Reg., tit.23, §5003). The 2015 UWMP is being amended only to report reduced reliance on the Delta and this action is separate from adoption of the 2020 UWMP and adoption of the 2021 WSCP.

AVEK is required to notify its retailers as well as cities, and counties within its service areas that it is preparing its 2020 UWMP, 2021 WSCP, and Appendix J of the 2015 UWMP at least 60 days prior to holding a public hearing. The public hearing is scheduled as part of a regularly scheduled AVEK Board meeting on June 8, 2021 at 5:30 p.m.

This serves as your official public hearing notice and intent to adopt the 2020 UWMP, 2021 WSCP and Appendix J of the 2015 UWMP before the July 1, 2021 deadline. A draft of each document will be available for review by May 25, 2021. AVEK will distribute a public draft review notification on or before May 25, 2021 with information on how to access the draft documents. Until that time, if you have any questions or comments regarding the documents or this process, please contact me at (661) 943‐3201 or [email protected].

Very truly yours,

Matthew Knudson, Assistant General Manager

D-1 AVEK 2020 UWMP Appendix D - Notifications

AVEK 2020 UWMP, 2021 WSCP, and 2015 UWMP Appendix J PUBLIC HEARING NOTIFICATION (April 5, 2021) RECIPIENT LIST

Water Retailer Notification Letter: Customer Notification Letter:

• Antelope Valley Country Club • Antelope Valley Water Storage, LLC • Boron Community Services District c/o WDS • California Water Service Company • CA Dept of Parks & Recreation Antelope Valley District (Poppy Reserve) • City of California City • Rancho Vista Golf Club • Desert Lake Community Services • Tejon Ranch Company District • US. Borax (Rio Tinto Minerals) • Desert Sage Apartments c/o Rex Public Notification Letter: Nishimura • Edgemont Acres Mutual Water Co. • Antelope Valley Watermaster • Edwards Air Force Base • Building Industry Association • El Dorado Mutual Water Co. • Littlerock Creek Irrigation District • Lake Elizabeth Mutual Water Co. • Mojave Water Agency • Landale Mutual Water Co. • North Edwards Water District • Los Angeles County Waterworks • Palmdale Water District Districts - Alhambra Cities/Counties Notification Letter: • Los Angeles County Waterworks Districts - Lancaster • City of Lancaster Planning Division • Mojave Public Utility District • City of Lancaster City Manager • Palm Ranch Irrigation District • City of Palmdale Planning Division • Quartz Hill Water District • City of Palmdale Public Works • Rosamond Community Services • Kern County Planning Department District • Los Angeles County Department of • Shadow Acres Mutual Water Co. Regional Planning Division • Sunnyside Farms Mutual Water Co. • Supervisor Kathryn Barger Antelope • West Side Park Mutual Water Co. Valley Field Office • White Fence Farms Mutual Water • Ventura County Resource Co. Management Agency Planning • White Fence Farms Mutual Water Division Co. #3

D-2 AVEK 2020 UWMP Appendix D - Notifications

Valley Press Ad

D-3

E

Appendix E: Adoption Resolutions

Antelope Valley-East Kern Water Agency 2020 Urban Water Management Plan May 2021 E DRAFT

F

Appendix F: Antelope Valley Groundwater Adjudication

The judgement can be found at: https://avwatermaster.net/resources/exhibits-charts/

Antelope Valley-East Kern Water Agency 2020 Urban Water Management Plan May 2021 F DRAFT

G

Appendix G: Antelope Valley Watermaster 2019 Annual Report

Each annual report can be found at: https://avwatermaster.net/new-annual-report/

Antelope Valley-East Kern Water Agency 2020 Urban Water Management Plan May 2021 G DRAFT

H

Appendix H: Water Shortage Contingency Plan

Antelope Valley-East Kern Water Agency 2020 Urban Water Management Plan May 2021 H DRAFT

ANTELOPE VALLEY- EAST KERN WATER AGENCY 2021 Water Shortage Contingency Plan

MAY 2021

Prepared by Water Systems Consulting, Inc.

Table of Contents

TABLE OF CONTENTS

List of Figures ...... ii List of Tables ...... ii 1. Water Shortage Contingency Plan ...... 1 1.1 Water Supply Reliability ...... 2 1.1.1 Normal Year ...... 3 1.1.2 Single Dry Year ...... 4 1.1.3 Five Consecutive Dry Years ...... 5 1.1.4 2021-2025 Drought Risk Assessment ...... 6 1.2 Annual Water Supply and Demand Assessment ...... 7 1.3 Water Shortage Stages ...... 8 1.3.1 Standard Water Shortage Level Crosswalk ...... 8 1.4 Shortage Response Actions ...... 9 1.4.1 Demand Reduction ...... 9 1.4.2 Supply Augmentation ...... 9 1.4.3 Emergency Response Plan ...... 9 1.4.4 Seismic Risk Assessment and Mitigation Plan ...... 11 1.5 Communication Protocols ...... 12 1.6 Legal Authorities ...... 12 1.7 Financial Consequences of WSCP ...... 12 1.8 WSCP Refinement Procedures ...... 13 1.9 Plan Adoption, Submittal, and Availability...... 13 1.10 References ...... 13 Attachment 1: AVEK Water Shortage Contingency Ordinance ...... I Attachment 2: Notifications and Notification List ...... II Attachment 3: Resolution of Adoption ...... III

Antelope Valley-East Kern Water Agency 2021 Water Shortage Contingency Plan May 2021 i DRAFT

Table of Contents

LIST OF FIGURES

Figure 1. AVEK Supply and Demand Projections, Normal Year ...... 3 Figure 2. AVEK Supply and Demand Projections, Single Dry Year ...... 4 Figure 3. AVEK Groundwater Bank Use vs. Storage Capacity during Five Consecutive Dry Years . 5 Figure 4. 2021–2025 AVEK Drought Reliability Assessment ...... 6 Figure 5. Water Shortage Level Crosswalk ...... 8

LIST OF TABLES

Table 1. WSCP Levels (DWR Table 8-1) ...... 8 Table 2. Demand Reduction Actions (DWR 8-2) ...... 9 Table 3. Supply Augmentation & Other Actions (DWR 8-3W) ...... 9

Antelope Valley-East Kern Water Agency 2021 Water Shortage Contingency Plan May 2021 ii DRAFT

Water Shortage Contingency Plan

Water Shortage Contingency Plan This WSCP is a detailed plan for how AVEK intends to respond to foreseeable and unforeseeable water shortages. A water shortage occurs when the water supply is reduced to a level that cannot support typical demand at any given time.

The Water Shortage Contingency Plan (WSCP) is used to provide guidance by identifying response actions to allow for efficient management of any water shortage with predictability and accountability. The tools in the WSCP enable the Antelope Valley-East Kern Water Agency (AVEK or Agency) to maintain reliable supplies and reduce the impact of supply interruptions due to extended drought or catastrophic supply interruptions.

The WSCP describes the following: • Water supply reliability analysis: Summarizes the AVEK water supply analysis and reliability, and identifies any key issues that may trigger a shortage condition. • Annual water supply and demand assessment procedures: Describes the key data inputs, evaluation criteria, and methodology for assessing the system’s reliability for the coming year and the steps to formally declare any water shortage levels and response actions. • Standard shortage stages: Establishes water shortage levels to clearly identify and prepare for shortages. • Shortage response actions: Describes the response actions that may be implemented or considered for each stage to reduce gaps between supply and demand as well as minimize social and economic impacts to the community. • Communication protocols: Describes communication protocols under each stage to ensure customers, the public, and government agencies are informed of shortage conditions and requirements. • Legal authority: Lists the legal ordinance that grants AVEK the authority to declare a water shortage and implement and enforce response actions. • Financial consequences of WSCP implementation: Describes the anticipated financial impact of implementing water shortage stages and identifies mitigation strategies to offset financial burdens. • WSCP refinement procedures: Describes the factors that may trigger updates to the WSCP and outlines how to complete an update. • Plan adoption, submittal, and availability: Describes the process for the WSCP adoption, submittal, and availability after each revision.

This WSCP was prepared in conjunction with AVEK’s 2020 Urban Water Management Plan (UWMP) and is a stand-alone document that can be modified as needed. This document is compliant with California Water Code (CWC) Section 10632 and incorporates guidance from the State of California Department of Water Resources (DWR) UWMP Guidebook. The plan is intended to provide guidance, rather than absolute direction, for action in response to water shortages and provide options to responsibly manage water shortages.

Antelope Valley-East Kern Water Agency 2021 Water Shortage Contingency Plan May 2021 1 DRAFT

Water Shortage Contingency Plan

1.1 Water Supply Reliability Water supply reliability reflects the Agency’s ability to meet the water needs of its retailers with water supplies under varying conditions. The analysis considers plausible hydrological and regulatory variability, climate conditions, and other factors that affect water supply and demand. The following is a concise narrative of the water supply reliability assessment. Chapter 7 of AVEK’s 2020 UWMP describes the reliability of the water supply by comparing supply and demand projections through 2045 for normal, single dry, and multiple dry years. The section also assesses the drought risk over the next five years (2021 to 2025) assuming the driest five-year period is repeated over the next five years. Refer to the 2020 UWMP for the full assessment. As demonstrated in this section, AVEK has sufficient supplies to meet demand in normal year, single dry, and multiple dry years.

As a wholesale water supplier, AVEK provides water to retail water suppliers in the Antelope Valley. AVEK’s supplies for this assessment consist of: • The State Water Project (SWP), which is managed by DWR. • Antelope Valley Groundwater Basin adjudicated rights, including production rights and imported water return flows, which are managed by the Antelope Valley Groundwater Basin Watermaster. • New supplemental water supplies acquired by AVEK for Los Angeles County Waterworks Districts (LACWD) per a memorandum of understanding (MOU) with LACWD for new growth within the LACWD service area.

AVEK’s water reliability goal is to provide a level of regional water reliability that supports customers’ water needs by developing groundwater banking programs to help increase the reliability of the Antelope Valley region’s water supplies. This is achieved by storing excess SWP water during wet periods in the local groundwater basin and recovering it for delivery to customers during dry and high- demand periods or during a disruption in deliveries from the SWP.

For the water supply reliability analysis, the following supply availability assumptions were applied for SWP Table A allocation for normal, single dry year, and multiple dry conditions for each of the City’s supplies: • Normal Year: Average yield based on DWR 2019 SWP Delivery Capability Report (DCR) (California Department of Water Resources 2020). • Single Dry Year: The lowest Table A allocation was 5% in 2014 and 2021 (as of May 2021). • Multiple Dry Year: The five-year historical sequence with the lowest available supply in the 2019 DCR was 1988 to 1992.

AVEK groundwater supplies are assumed to consist of 3,550 acre-feet per year (AFY) of production rights from the adjudication and 800 AFY of imported water return flows based on 2016 to 2020 return flows. Groundwater rights are not impacted by short-term drought conditions, so normal year groundwater yield assumptions are applied. In years with low SWP Table A allocations, the remainder of demand is met with groundwater bank supplies.

Antelope Valley-East Kern Water Agency 2021 Water Shortage Contingency Plan May 2021 2 DRAFT

Water Shortage Contingency Plan

1.1.1 Normal Year Average SWP Table A allocation is projected to decrease from 58% in 2020 to 52% in 2040 (California Department of Water Resources, 2020). Total normal year AVEK supplies are shown in Figure 1. Based on these assumptions, AVEK has sufficient supplies in normal years and could use available supplies to build groundwater storage for dry periods. For example, SWP water could be recharged when available, or unused groundwater rights can be carried over for use in future years.

Figure 1. AVEK Supply and Demand Projections, Normal Year

120,000

97,010 Total AVEK Supplies 100,000 93,790 94,030 94,430 91,080

4,890 9,780 12,190 14,760 17,340 4,350 4,350 80,000 4,350 4,350 4,350

60,000 AFY 57,590 55,210 Total AVEK Demand 50,990 51,880 44,440 40,000 New Supply (per LACWD MOU) AVEK Groundwater 20,000

AVEK SWP Table A 81,840 79,660 77,490 75,320 75,320 0 2025 2030 2035 2040 2045

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Water Shortage Contingency Plan

1.1.2 Single Dry Year Single dry year yield for SWP water is based on actual 2014 and 2021 allocations (as of May 2021) of 5%. Groundwater rights are not impacted by short-term drought conditions, so normal year groundwater yield assumptions are applied. The new supplemental water supplies (per LACWD MOU) are assumed to have greater reliability than SWP Table A supplies based on the mix of supplies. The remainder of demand is met with groundwater in storage. AVEK’s banking recovery production target is at least enough pumping capacity to meet demands in a year with SWP Table A allocations of 10%. As shown in Figure 2, groundwater bank supplies enable AVEK to meet its demands.

Figure 2. AVEK Supply and Demand Projections, Single Dry Year

70,000

60,000 57,590 Total AVEK Demand 55,210 50,990 51,880 50,000 44,440 28,660 40,000 28,860 28,100 29,620 AFY 30,000 27,960

AVEK Groundwater Bank 20,000 17,340 14,760 12,190 New Supply 9,780 (per LACWD MOU) 4,890 AVEK Groundwater 10,000 4,350 4,350 4,350 4,350 4,350 AVEK SWP Table A 7,240 7,240 7,240 7,240 7,240 0 2025 2030 2035 2040 2045

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Water Shortage Contingency Plan

1.1.3 Five Consecutive Dry Years For multiple dry years, SWP water availability is based on the five-year period with the lowest SWP simulated yield from the 2019 SWP DCR (1988–1992) and the following annual Table A allocation: • Year 1 (1988) 12.3% • Year 2 (1989) 32.2% • Year 3 (1990) 13.3% • Year 4 (1991) 25.6% • Year 5 (1992) 18.0%

Similar to single dry year, new supplemental water supplies (per LACWD MOU) are assumed to have greater reliability than SWP Table A supplies, groundwater rights are not impacted by an extended drought, and groundwater bank supplies are used to meet remaining demands. As shown in Figure 3, additional groundwater bank supplies would be available if the five-year drought continued and sufficient water is in storage at the beginning of an extended drought.

Figure 3. AVEK Groundwater Bank Use vs. Storage Capacity during Five Consecutive Dry Years

160,000

140,000 137,650 131,190 120,000 119,850 122,220 Total Use of Groundwater Bank 100,000 102,680

Target Storage Capacity

AF 80,000

60,000

40,000

20,000 40,740 43,730 45,880 34,230 39,950

0 2025-2029 2030-2034 2035-2039 2040-2044 2045-2049

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Water Shortage Contingency Plan

1.1.4 2021-2025 Drought Risk Assessment The Drought Risk Assessment for the upcoming five years (2021–2025) is based on the five-year period with the lowest SWP simulated yield from the 2019 SWP DCR (1988–1992). Figure 4 presents the projected supplies used to meet demands and the remaining available supply each year. AVEK currently has roughly 90,000 acre-feet (AF) of SWP water stored within its banks for future recovery and is implementing infrastructure projects to expand its capacity to recharge water, recover water, and distribute recovered water. As shown in the figure, AVEK still would have over 40,000 AF of groundwater remaining in storage at the end of a five-year drought that starts in 2021.

Figure 4. 2021–2025 AVEK Drought Reliability Assessment

140,000

120,000 Groundwater Bank Storage (at end of year) 100,000 SWP from Groundwater Bank 74,300

80,000 New Supply 74,300 58,360 58,360 (per LACWD MOU) 49,210 AFY or AF or AFY 60,000 AVEK Groundwater

SWP, Table A 42,590 43,340 44,440 40,000 39,060 40,930

AVEK Demand 20,000

0 2021 2022 2023 2024 2025

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Water Shortage Contingency Plan

1.2 Annual Water Supply and Demand Assessment As established by CWC Section 10632.1, urban water suppliers must conduct annual water supply and demand assessments, and submit an annual water shortage assessment report to DWR with information on anticipated shortages, triggered shortage response actions, and compliance and enforcement actions consistent with the WSCP. Beginning July 1, 2022, AVEK must prepare its annual water supply and demand assessment and submit an Annual Water Shortage Assessment Report to DWR. The Annual Water Shortage Assessment Report will be due by July 1 of every year.

Per CWC, the annual assessment must include: • The written decision-making process AVEK will use each year to determine its water supply reliability. • The key data inputs and assessment methodology used to evaluate the supplier’s water supply reliability for the current year and one dry year, including: − Current year unconstrained demand − Current year available supply in the current year and one dry year − Existing infrastructure capabilities and plausible constraints − A defined set of locally applicable evaluation criteria that are consistently relied upon for each annual water supply and demand assessment − A description and quantification of each source of water supply

AVEK regularly assess its water supply and demands. The following are AVEK’s targets and goals when making decisions on managing AVEK’s water supplies: • Storage goals − SWP carryover goal of 15,000 to 20,000 AF in the event the following water year is below average or dry − Local groundwater storage goal to have enough local groundwater storage to meet customer demands for three years with a 10% SWP allocation for those three years • During the fourth quarter of each year, AVEK requests a five-year demand projection from each of its customers. AVEK uses this information to calculate what the projected annual demand will be for AVEK and tracks the projected versus actual demand to adjust the plan for that year. • AVEK’s General Manager, Assistant General Manager, Water Resources Manager, and Operations Manager meet regularly to review the available water supplies and sources, customer demands, and transfer/exchange statuses. Decisions are discussed and made as to which water sources will be used and what facilities will be used to treat/distribute the water to meet the demands of its customers.

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Water Shortage Contingency Plan

1.3 Water Shortage Stages In the event of water supply shortages, the Agency will make water delivery reductions per this WSCP. The stages of action are summarized in Table 1. Actions to be taken as a result of a catastrophic water supply shortage are discussed in Section 1.4.4.

Table 1. WSCP Levels (DWR Table 8-1)

Percent Shortage Range Shortage Level (Numerical Value as a Percent) Water Supply Condition

1 Up to 50% Reduction in SWP Allocation below Current Demand

Reduction in SWP Allocation below Current Demand or 2 >50% Catastrophic water supply shortage

1.3.1 Standard Water Shortage Level Crosswalk CWC Section 10632(a)(3)(A) includes six standard water shortage levels corresponding to progressive ranges of up to 10%, 20%, 30%, 40%, and 50% shortages and greater than 50% shortages. If the supplier’s water shortage levels do not correspond with the six standard levels, a crosswalk between the supplier’s stages and the standard levels is required for compliance, as shown in Figure 5.

Figure 5. Water Shortage Level Crosswalk

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Water Shortage Contingency Plan

1.4 Shortage Response Actions CWC Section 10632 (a)(4) requires the WSCP to specify shortage response actions that align with the defined shortage levels. The Agency has defined specific shortage response actions that align with the defined shortage levels in Table H-1 and Figure H-5. These shortage response actions were developed with consideration to the system infrastructure and operations changes, supply augmentation responses, customer-class- or water-use-specific demand reduction initiatives, and increasingly stringent water use prohibitions.

1.4.1 Demand Reduction Although AVEK does not have the authority to implement consumer-level reduction methods, the Agency has adopted some consumption reduction measures to help retail water suppliers reduce water usage. These are listed in Table 2 and described in more detail in the 2020 UWMP Chapter 9, Demand Management Measures.

Table 2. Demand Reduction Actions (DWR 8-2)

DEMAND HOW MUCH IS THIS SHORTAGE REDUCTION GOING TO REDUCE THE ADDITIONAL EXPLANATION OR PENALTY, CHARGE, OR LEVEL ACTIONS SHORTAGE GAP?1 REFERENCE OTHER ENFORCEMENT Expand Public Community outreach that includes All Information Up to 50% educational information and water No Campaign conservation tips Note: 1.Reduction in the shortage gap is estimated and can vary significantly.

1.4.2 Supply Augmentation The SWP conveyance infrastructure enables AVEK to convey supplemental water purchases to augment drought year supplies. Refer to the 2020 UWMP Section 6.2 for more information on supplemental water purchases and transfers. Supply augmentation actions are described in Table 3. These augmentations represent short-term management objectives triggered during a water shortage and do not overlap with the long-term new water supply development or supply reliability enhancement projects.

Table 3. Supply Augmentation & Other Actions (DWR 8-3W)

SUPPLY AUGMENTATION METHODS HOW MUCH IS THIS AND OTHER ACTIONS BY WATER GOING TO REDUCE SHORTAGE LEVEL SUPPLIER THE SHORTAGE GAP? ADDITIONAL EXPLANATION OR REFERENCE Agency Discretion Water Purchases and Transfers Varying Supplemental water purchases from SWP

1.4.3 Emergency Response Plan AVEK maintains emergency plans for activities required in the event there is an interruption in the SWP water supply or there is a major mechanical or electrical failure in one of the water treatment plants. In September 2020, AVEK adopted an Emergency Response Plan (ERP) in alignment with America’s Water Infrastructure Act of 2018. An ERP describes strategies, resources, plans, and procedures

Antelope Valley-East Kern Water Agency 2021 Water Shortage Contingency Plan May 2021 9 DRAFT Water Shortage Contingency Plan

utilities can use to prepare for and respond to an incident, natural or man-made, that threatens life, property, or the environment. The ERP is not attached to this WSCP due to sensitive information included, but key aspects are summarized in this section. The emergency activities undertaken by AVEK depend upon the severity of the problem and how quickly it can be remedied. Response to a catastrophic event will always include contact and coordination with AVEK’s customers. If the emergency can be resolved within the available water storage time frame, only a few of the larger customers need to be notified of the temporary decrease in water supply. If there will be a stoppage in the raw water deliveries to the various water treatment plants, all customers (Municipal and Industrial (M&I) and agriculture) will be notified of the stoppage and how soon water deliveries may be resumed.

Possible catastrophes affecting water supply may include: • Widespread power outage • Local earthquake • Agency treatment plant shutdown due to vital component failure • Aqueduct failure due to earthquake or other circumstances • Delta levee failure

In the event of power loss, AVEK has permanent emergency power generation equipment that automatically starts to maintain water treatment operations. In the event of an earthquake, AVEK personnel will survey and assess damage and respond accordingly with shutdowns and repairs. Damaged Agency treatment plant components, whether mechanical or electrical, may be able to be circumvented due to the duplication of pumping and operations systems or the availability of manual override controls. If raw water deliveries to water treatment plants are temporarily stopped, treated water from other plants may be able to be rerouted to the affected areas via interconnecting pipeline systems. Recovery of previously banked groundwater can be used to supply water in the event of SWP outages. The magnitude of reduced water deliveries and length of time before resumption of full water availability will determine the extent of customer (M&I and agriculture) notification and activities required by AVEK staff. In the event of a long-term outage of SWP supplies, AVEK will coordinate with the retail water agencies to develop and implement appropriate regional water conservation measures. Failure of the aqueduct or Delta levees could result in significant outages and potential interruption in SWP service to AVEK for six months or longer. DWR has estimated that, in the event of a major earthquake in or near the Delta, regular water supply deliveries from the SWP could be interrupted for up to three years, posing a substantial risk to the California business economy. Accordingly, a post- event strategy has been developed which would provide necessary water supply protections. The plan has been coordinated through DWR, the Army Corps of Engineers (Corps), Bureau of Reclamation, California Office of Emergency Services (Cal OES), Metropolitan Water District of Southern California, and State Water Contractors. Full implementation of the plan would enable resumption of at least partial deliveries from the SWP in less than six months. DWR has developed the Delta Flood Emergency Management Plan to provide strategies for a response to Delta levee failures, addressing a range of failures up to and including earthquake-induced multiple island failures during dry conditions when the volume of flooded islands and saltwater intrusion is large. Under such severe conditions, the plan includes a strategy to establish an emergency freshwater pathway from the central Delta along Middle River and Victoria Canal to the export pumps in the south Delta. The plan includes the pre-positioning of emergency construction materials at existing and new stockpiles and warehouse sites in the Delta, and development of tactical modeling tools (DWR Emergency Response Tool) to predict levee repair logistics, water quality conditions, and timelines of levee repair and suitable water quality to restore exports. The Delta Flood Emergency Management Plan has been extensively coordinated with state, federal, and local emergency response agencies. Antelope Valley-East Kern Water Agency 2021 Water Shortage Contingency Plan May 2021 10 DRAFT

Water Shortage Contingency Plan

DWR, in conjunction with local agencies, the Corps, and Cal OES, regularly conducts simulated and field exercises to test and revise the plan under real-time conditions. DWR and the Corps provide vital Delta region response to flood and earthquake emergencies, complementing an overall Cal OES structure. Cal OES is preparing its Northern California Catastrophic Flood Response Plan, which incorporates the DWR Delta Flood Emergency Management Plan. These agencies use a unified command structure and response and recovery framework. DWR and the Corps, through a Draft Delta Emergency Operations Integration Plan (April 2015), would integrate personnel and resources during emergency operations. The DWR Delta Levees Subvention Program has prioritized, funded, and implemented levee improvements along the emergency freshwater pathway and other water supply corridors in the central and south Delta region. These efforts have been complementary to the DWR Delta Flood Emergency Management Plan, which, along with use of pre-positioned emergency flood fight materials in the Delta, relies on the pathway and other levees providing reasonable seismic performance to facilitate restoration of the freshwater pathway after a severe earthquake. Together, these two DWR programs have been successful in implementing a coordinated strategy of emergency preparedness for the benefit of SWP and Central Valley Project (CVP) export systems. Significant improvements to the central and south Delta levee systems along the Old and Middle Rivers began in 2010 and are continuing to the present time at Holland Island, Bacon Island, Upper and Lower Jones Tracts, Palm Tract, and Orwood Tract. This complements substantially improved levees at Mandeville and McDonald Islands and portions of Victoria and Union Islands. Together, levee improvements along the pathway and Old River levees consisting of crest raising, crest widening, landside slope fill, and toe berms meet the needs of local reclamation districts and substantially improve seismic stability to reduce levee slumping and create a more robust flood-fighting platform.

1.4.4 Seismic Risk Assessment and Mitigation Plan AVEK completed a Risk and Resilience Assessment (R.E. Patterson and Associates, March 2020) in 2020 in alignment with America’s Water Infrastructure Act of 2018 and conducted a focused seismic assessment as part of the 2020 AVEK Water System Master Plan (Carollo, September 2020). These documents, along with the AVEK ERP (discussed in the previous section) address the risk assessment and emergency response requirements for UWMPs in the water code.

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Water Shortage Contingency Plan

1.5 Communication Protocols AVEK strives to be proactive in communicating work strategy and conservation efforts with its retail customers. To support these efforts, AVEK developed a Strategic Communications Plan in 2020. For water shortages, AVEK would focus on key stakeholders, which include AVEK customers (public agencies, agricultural entities, water purveyors, and individuals), agency directors and staff, and State Water Contractors. AVEK would also engage with secondary stakeholders, such as constituents, government agencies (local, state, and federal), and elected officials (local, state, and federal). Engagement would occur through owned media and earned media. Owned media is any communication channel that the Agency has control over, such as its website, social media pages, newsletters, or e-mail outreach. Owned media can be used to disseminate information and resonate messages.

The following media outlets have been identified and prioritized: • Website, including news bulletins, press releases, news stories, and newsletter • Newsletter • Videos and photos • Social media channels, including Facebook, Twitter, and LinkedIn

In addition, AVEK would emphasize water shortage conditions and measures at events. Earned media refers to publicity that is gained through unpaid promotional efforts, such as press placements or social media content shared by others. The Agency maintains a media distribution list.

1.6 Legal Authorities In the event of water supply shortages, the Agency will make water delivery reduction per the Agency law for allocations and the Agency’s water shortage contingency ordinance (Ordinance O-07-2), which is included in Attachment 1. AVEK can declare a water shortage emergency in accordance with CWC Chapter 3 (commencing with Section 350) of Division 1 general provision regarding water shortage emergencies. AVEK will coordinate with any city or county within which it provides water supply services for the possible proclamation of a local emergency under California Government Code, California Emergency Services Act (Article 2, Section 8558).

1.7 Financial Consequences of WSCP Revenues collected by the Agency are currently used to fund operation and maintenance of the existing facilities and fund new capital improvements. In dry years, the Agency will estimate a projected range of water sales versus shortage stage to quantify the impact the shortage stage may have on projected revenues and expenses. Revenue reductions and an increase in expenses may occur during implementation of the water shortage contingency plan. The magnitude of the revenue reduction and expenditure increase will depend on the severity of the shortage. In some cases, AVEK may be able to absorb the revenue shortfall/expenditure increase by reallocating existing funds, such as delaying some capital projects. For more severe events, the Agency may enact a rate adjustment to its customers.

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Water Shortage Contingency Plan

1.8 WSCP Refinement Procedures AVEK intends to use this WSCP as an adaptive management plan to respond to foreseeable and unforeseeable water shortages. The WSCP is used to provide guidance to the Agency, its staff, and the public by identifying response actions to allow for efficient management of any water shortage with predictability and accountability. To maintain a useful and efficient standard of practice in water shortage conditions, the requirements, criteria, and response actions need to be continuously evaluated and improved upon to make sure the WSCP provides the tools to maintain reliable supplies and reduce the impacts of supply shortages. AVEK deliveries are entirely metered. The meter readings will be used to monitor the actual reductions in deliveries to AVEK’s customers in accordance with the water shortage contingency plan to measure effectiveness of implemented strategies.

1.9 Plan Adoption, Submittal, and Availability Per CWC Section 10632 (a)(c), AVEK sent letters of notification of preparation of the 2021 WSCP to all necessary cities, counties, retail water agencies, and interested parties within its service areas 60 days prior to the public hearing. Copies of the notification letter and distributions list is included in Attachment 2. AVEK made the draft 2021 WSCP available for public review and held a public hearing on June 8, 2021. The notice of the public review hearing (Attachment 2) was advertised in the Valley Press on May 26, 2021 and June 2, 2021. The 2020 UWMP, 2021 WSCP, and 2015 UWMP addendum were adopted by AVEK’s Board of Directors on June 22, 2021. A copy of the Resolution of Adoption is included as Attachment 3. Once the 2021 WSCP is adopted, a copy will be submitted to the California State Library, DWR, and all cities and counties within 30 days of adoption. The Agency will also have a physical copy of the 2021 WSCP available for public review at the AVEK Office (see address below) during normal business hours.

The WSCP also will be posted on the Agency’s website at www.avek.org.

Antelope Valley-East Kern Water Agency 6500 W. Avenue N Palmdale, CA 93551

Based on DWR’s review of the WSCP, AVEK may make any amendments in its adopted WSCP as required and directed by DWR. If AVEK revises its WSCP after it is approved by DWR, an electronic copy of the revised WSCP will be submitted to DWR within 30 days of its adoption.

1.10 References California Department of Water Resources. (2020). 2019 State Water Project Delivery Capability Report. Carollo. (September 2020). DRAFT AVEK Water System Master Plan. R.E. Patterson and Associates. (March 2020). AVEK Risk and Resilience Assessment.

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1

Attachment 1: AVEK Water Shortage Contingency Ordinance

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ORDINANCE O‐07‐2: AVEK WATER SHORTAGE CONTINGENCY PLAN

APPENDIX H

APPENDIX H

APPENDIX H

APPENDIX H EXHIBIT A

§ 61.1 Distribution and apportionment of water purchased from State, etc. The agency shall whenever practicable, distribute and apportion the water purchased from the State of California or water obtained from any other source as equitably as possible on the basis of total payment by a district or geographical area within the agency regardless of its present status, of taxes, in relation that such payment bears to the total taxes and assessments collected from all other areas. It is the intent of this section to assure each area or district its fair share of water based upon the amounts paid into the agency, as they bear relation to the total amount collected by the agency.

APPENDIX H EXHIBIT B

APPENDIX H EXHIBIT C

Kern County % Billiton Exploration U.S.A. 0.24 Boron CSD 4.66 City of California City 9.88 Desert Lake CSD 1.47 Desert Sage Apartments 0.09 Edgemont Acres MWC 0.31 Edwards AFB 37.79 Mojave Public Utility District 1.01 Rosamond CSD 17.88 US Borax 26.67

Los Angeles County % Antelope Valley Country Club 0.35 California Water Service Co 0.58 Landale MWC 0.13 Los Angeles County Waterworks Districts 84.98 Palm Ranch Irrigation District 0.71 Quartz Hill Water District 8.42 Shadow Acres MWC 0.61 Sunnyside Farms MWC 0.59 White Fence Farms MWC 1.71 Lake Elizabeth MWC 1.91

APPENDIX H Appendix 1 to the Water Shortage Contingency Plan

Water Supply Shortage Stages and Conditions

1 Reduction in SWP Allocation Below Current Demand 1 % 2 Reduction in SWP Allocation Below Current Demand 50% 1 Reduction in SWP Allocation Below Current Demand 1 % 2 Reduction in SWP Allocation Below Current Demand 50%

APPENDIX H

2

Attachment 2: Notifications and Notification List

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AVEK 2020 UWMP Appendix D - Notifications

April 6, 2021

NOTICE OF PUBLIC HEARING ON THE ANTELOPE VALLEY‐EAST KERN WATER AGENCY DRAFT 2020 URBAN WATER MANAGEMENT PLAN, DRAFT 2021 WATER SHORTAGE CONTINGENCY PLAN, AND DRAFT APPENDIX J TO THE 2015 UWMP

Dear Recipient,

The Antelope Valley‐East Kern Water Agency (AVEK) is in the process of preparing its 2020 Urban Water Management Plan (UWMP) and 2021 Water Shortage Contingency Plan (WSCP) as required by the Urban Water Management Planning Act (Act). In addition, AVEK is preparing an Appendix to both the 2015 UWMP and 2020 UWMP to demonstrate consistency with the Delta Plan Policy WR P1, Reduced Reliance on the Delta Through Improved Regional Water Self‐Reliance (California Code Reg., tit.23, §5003). The 2015 UWMP is being amended only to report reduced reliance on the Delta and this action is separate from adoption of the 2020 UWMP and adoption of the 2021 WSCP.

AVEK is required to notify its retailers as well as cities, and counties within its service areas that it is preparing its 2020 UWMP, 2021 WSCP, and Appendix J of the 2015 UWMP at least 60 days prior to holding a public hearing. The public hearing is scheduled as part of a regularly scheduled AVEK Board meeting on June 8, 2021 at 5:30 p.m.

This serves as your official public hearing notice and intent to adopt the 2020 UWMP, 2021 WSCP and Appendix J of the 2015 UWMP before the July 1, 2021 deadline. A draft of each document will be available for review by May 25, 2021. AVEK will distribute a public draft review notification on or before May 25, 2021 with information on how to access the draft documents. Until that time, if you have any questions or comments regarding the documents or this process, please contact me at (661) 943‐3201 or [email protected].

Very truly yours,

Matthew Knudson, Assistant General Manager

D-1 AVEK 2020 UWMP Appendix D - Notifications

AVEK 2020 UWMP, 2021 WSCP, and 2015 UWMP Appendix J PUBLIC HEARING NOTIFICATION (April 5, 2021) RECIPIENT LIST

Water Retailer Notification Letter: Customer Notification Letter:

• Antelope Valley Country Club • Antelope Valley Water Storage, LLC • Boron Community Services District c/o WDS • California Water Service Company • CA Dept of Parks & Recreation Antelope Valley District (Poppy Reserve) • City of California City • Rancho Vista Golf Club • Desert Lake Community Services • Tejon Ranch Company District • US. Borax (Rio Tinto Minerals) • Desert Sage Apartments c/o Rex Public Notification Letter: Nishimura • Edgemont Acres Mutual Water Co. • Antelope Valley Watermaster • Edwards Air Force Base • Building Industry Association • El Dorado Mutual Water Co. • Littlerock Creek Irrigation District • Lake Elizabeth Mutual Water Co. • Mojave Water Agency • Landale Mutual Water Co. • North Edwards Water District • Los Angeles County Waterworks • Palmdale Water District Districts - Alhambra Cities/Counties Notification Letter: • Los Angeles County Waterworks Districts - Lancaster • City of Lancaster Planning Division • Mojave Public Utility District • City of Lancaster City Manager • Palm Ranch Irrigation District • City of Palmdale Planning Division • Quartz Hill Water District • City of Palmdale Public Works • Rosamond Community Services • Kern County Planning Department District • Los Angeles County Department of • Shadow Acres Mutual Water Co. Regional Planning Division • Sunnyside Farms Mutual Water Co. • Supervisor Kathryn Barger Antelope • West Side Park Mutual Water Co. Valley Field Office • White Fence Farms Mutual Water • Ventura County Resource Co. Management Agency Planning • White Fence Farms Mutual Water Division Co. #3

D-2 AVEK 2020 UWMP Appendix D - Notifications

Valley Press Ad

D-3

3

Attachment 3: Resolution of Adoption

(to be included in Final WSCP)

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